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Single Cell Analysis of Bistable Expression of Pathogenicity Island 1 and the Flagellar Regulon in Salmonella enterica.

ABSTRACT: Bistable expression of the Salmonella enterica pathogenicity island 1 (SPI-1) and the flagellar network (Flag) has been described previously. In this study, simultaneous monitoring of OFF and ON states in SPI-1 and in the flagellar regulon reveals independent switching, with concomitant formation of four subpopulations: SPI-1^OFF Flag^OFF, SPI-1^OFF Flag^ON, SPI-1^ON Flag^OFF, and SPI-1^ON Flag^ON. Invasion assays upon cell sorting show that none of the four subpopulations is highly invasive, thus raising the possibility that Flag^OFF cells might contribute to optimal invasion as previously proposed for SPI-1^OFF cells. Time lapse microscopy observation indicates that expression of the flagellar regulon contributes to the growth impairment previously described in SPI-1^ON cells. As a consequence, growth resumption in SPI-1^ON Flag^ON cells requires switching to both SPI-1^OFF and Flag^OFF states.

SUBMITTER: Sanchez-Romero MA

PROVIDER: S-EPMC7909444 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Single Cell Analysis of Bistable Expression of Pathogenicity Island 1 and the Flagellar Regulon in Salmonella enterica.

Sánchez-Romero María Antonia MA Casadesús Josep J

Microorganisms 20210120 2

Bistable expression of the Salmonella enterica pathogenicity island 1 (SPI-1) and the flagellar network (Flag) has been described previously. In this study, simultaneous monitoring of OFF and ON states in SPI-1 and in the flagellar regulon reveals independent switching, with concomitant formation of four subpopulations: SPI-1OFF FlagOFF, SPI-1OFF FlagON, SPI-1ON FlagOFF, and SPI-1ON FlagON. Invasion as ...[more]

PMID: 33498391

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