The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.

In many Gram-negative bacteria, the stress sigma factor of RNA polymerase, σS/RpoS, remodels global gene expression to reshape the physiology of quiescent cells and ensure their survival under non-optimal growth conditions. In the foodborne pathogen Salmonella enterica serovar Typhimurium, σS is als...

Full description

Bibliographic Details
Main Authors: Selma Metaane, Véronique Monteil, Sophie Ayrault, Louise Bordier, Corinne Levi-Meyreuis, Françoise Norel
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2022-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0265511
_version_ 1811306750806065152
author Selma Metaane
Véronique Monteil
Sophie Ayrault
Louise Bordier
Corinne Levi-Meyreuis
Françoise Norel
author_facet Selma Metaane
Véronique Monteil
Sophie Ayrault
Louise Bordier
Corinne Levi-Meyreuis
Françoise Norel
author_sort Selma Metaane
collection DOAJ
description In many Gram-negative bacteria, the stress sigma factor of RNA polymerase, σS/RpoS, remodels global gene expression to reshape the physiology of quiescent cells and ensure their survival under non-optimal growth conditions. In the foodborne pathogen Salmonella enterica serovar Typhimurium, σS is also required for biofilm formation and virulence. We have previously identified sRNAs genes positively controlled by σS in Salmonella, including the two paralogous sRNA genes, ryhB1 and ryhB2/isrE. Expression of ryhB1 and ryhB2 is repressed by the ferric uptake regulator Fur when iron is available. In this study, we show that σS alleviates Fur-mediated repression of the ryhB genes and of additional Fur target genes. Moreover, σS induces transcription of the manganese transporter genes mntH and sitABCD and prevents their repression, not only by Fur, but also by the manganese-responsive regulator MntR. These findings prompted us to evaluate the impact of a ΔrpoS mutation on the Salmonella ionome. Inductively coupled plasma mass spectrometry analyses revealed a significant effect of the ΔrpoS mutation on the cellular concentration of manganese, magnesium, cobalt and potassium. In addition, transcriptional fusions in several genes involved in the transport of these ions were regulated by σS. This study suggests that σS controls fluxes of ions that might be important for the fitness of quiescent cells. Consistent with this hypothesis, the ΔrpoS mutation extended the lag phase of Salmonella grown in rich medium supplemented with the metal ion chelator EDTA, and this effect was abolished when magnesium, but not manganese or iron, was added back. These findings unravel the importance of σS and magnesium in the regrowth potential of quiescent cells.
first_indexed 2024-04-13T08:51:09Z
format Article
id doaj.art-9008862b773541a1a85c88578281934b
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-13T08:51:09Z
publishDate 2022-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-9008862b773541a1a85c88578281934b2022-12-22T02:53:28ZengPublic Library of Science (PLoS)PLoS ONE1932-62032022-01-01173e026551110.1371/journal.pone.0265511The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.Selma MetaaneVéronique MonteilSophie AyraultLouise BordierCorinne Levi-MeyreuisFrançoise NorelIn many Gram-negative bacteria, the stress sigma factor of RNA polymerase, σS/RpoS, remodels global gene expression to reshape the physiology of quiescent cells and ensure their survival under non-optimal growth conditions. In the foodborne pathogen Salmonella enterica serovar Typhimurium, σS is also required for biofilm formation and virulence. We have previously identified sRNAs genes positively controlled by σS in Salmonella, including the two paralogous sRNA genes, ryhB1 and ryhB2/isrE. Expression of ryhB1 and ryhB2 is repressed by the ferric uptake regulator Fur when iron is available. In this study, we show that σS alleviates Fur-mediated repression of the ryhB genes and of additional Fur target genes. Moreover, σS induces transcription of the manganese transporter genes mntH and sitABCD and prevents their repression, not only by Fur, but also by the manganese-responsive regulator MntR. These findings prompted us to evaluate the impact of a ΔrpoS mutation on the Salmonella ionome. Inductively coupled plasma mass spectrometry analyses revealed a significant effect of the ΔrpoS mutation on the cellular concentration of manganese, magnesium, cobalt and potassium. In addition, transcriptional fusions in several genes involved in the transport of these ions were regulated by σS. This study suggests that σS controls fluxes of ions that might be important for the fitness of quiescent cells. Consistent with this hypothesis, the ΔrpoS mutation extended the lag phase of Salmonella grown in rich medium supplemented with the metal ion chelator EDTA, and this effect was abolished when magnesium, but not manganese or iron, was added back. These findings unravel the importance of σS and magnesium in the regrowth potential of quiescent cells.https://doi.org/10.1371/journal.pone.0265511
spellingShingle Selma Metaane
Véronique Monteil
Sophie Ayrault
Louise Bordier
Corinne Levi-Meyreuis
Françoise Norel
The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
PLoS ONE
title The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
title_full The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
title_fullStr The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
title_full_unstemmed The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
title_short The stress sigma factor σS/RpoS counteracts Fur repression of genes involved in iron and manganese metabolism and modulates the ionome of Salmonella enterica serovar Typhimurium.
title_sort stress sigma factor σs rpos counteracts fur repression of genes involved in iron and manganese metabolism and modulates the ionome of salmonella enterica serovar typhimurium
url https://doi.org/10.1371/journal.pone.0265511
work_keys_str_mv AT selmametaane thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT veroniquemonteil thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT sophieayrault thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT louisebordier thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT corinnelevimeyreuis thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT francoisenorel thestresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT selmametaane stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT veroniquemonteil stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT sophieayrault stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT louisebordier stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT corinnelevimeyreuis stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium
AT francoisenorel stresssigmafactorssrposcounteractsfurrepressionofgenesinvolvedinironandmanganesemetabolismandmodulatestheionomeofsalmonellaentericaserovartyphimurium