Loss of CorA, the primary magnesium transporter of Salmonella, is alleviated by MgtA and PhoP-dependent compensatory mechanisms - Institut Pasteur Accéder directement au contenu
Article Dans Une Revue PLoS ONE Année : 2023

Loss of CorA, the primary magnesium transporter of Salmonella, is alleviated by MgtA and PhoP-dependent compensatory mechanisms

Résumé

In many Gram-negative bacteria, the stress sigma factor of RNA polymerase, σ S /RpoS, remodels global gene expression to reshape the physiology of stationary phase cells and ensure their survival under non-optimal growth conditions. In the foodborne pathogen Salmonella enterica serovar Typhimurium, σ S is also required for biofilm formation and virulence. We have recently shown that a Δ rpoS mutation decreases the magnesium content and expression level of the housekeeping Mg 2+ -transporter CorA in stationary phase Salmonella . The other two Mg 2+ -transporters of Salmonella are encoded by the PhoP-activated mgtA and mgtB genes and are expressed under magnesium starvation. The σ S control of corA prompted us to evaluate the impact of CorA in stationary phase Salmonella cells, by using global and analytical proteomic analyses and physiological assays. The Δ corA mutation conferred a competitive disadvantage to exit from stationary phase, and slightly impaired motility, but had no effect on total and free cellular magnesium contents. In contrast to the wild-type strain, the Δ corA mutant produced MgtA, but not MgtB, in the presence of high extracellular magnesium concentration. Under these conditions, MgtA production in the Δ corA mutant did not require PhoP. Consistently, a Δ mgtA , but not a Δ phoP , mutation slightly reduced the magnesium content of the Δ corA mutant. Synthetic phenotypes were observed when the Δ phoP and Δ corA mutations were combined, including a strong reduction in growth and motility, independently of the extracellular magnesium concentration. The abundance of several proteins involved in flagella formation, chemotaxis and secretion was lowered by the Δ corA and Δ phoP mutations in combination, but not alone. These findings unravel the importance of PhoP-dependent functions in the absence of CorA when magnesium is sufficient. Altogether, our data pinpoint a regulatory network, where the absence of CorA is sensed by the cell and compensated by MgtA and PhoP- dependent mechanisms.
Fichier principal
Vignette du fichier
journal.pone.0291736.pdf (2.37 Mo) Télécharger le fichier
Origine Publication financée par une institution
Licence

Dates et versions

pasteur-04582026 , version 1 (17-06-2024)

Licence

Identifiants

Citer

Selma Metaane, Véronique Monteil, Thibaut Douché, Quentin Giai Gianetto, Mariette Matondo, et al.. Loss of CorA, the primary magnesium transporter of Salmonella, is alleviated by MgtA and PhoP-dependent compensatory mechanisms. PLoS ONE, 2023, 18 (9), pp.e0291736. ⟨10.1371/journal.pone.0291736⟩. ⟨pasteur-04582026⟩
0 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More