Expression of mgtA encoding a magnesium transporter is activated in the absence of the main Mg2+ transporter CorA in Salmonella

Salmonella imports magnesium via three known transporters, the widely conserved CorA transporter and the MgtA and MgtB P-type ATPases. CorA is expressed under various growth conditions whereas the other two magnesium transporters, MgtA and MgtB, are expressed under conditions of magnesium starvation under the positive control of the PhoP-PhoQ regulatory system.                        Our recent results suggest that production of MgtA, but not that of MgtB, is activated in the absence of the main Mg2+ transporter CorA (Metaane et al 2022, 2023 )                        This hypothesis was further validated in this study by using transcriptional and translational lacZ fusions in the mgtA and mgtB genes. In addition, our data suggest that regulation of expression of MgtA in the absence of CorA is post-transcriptional .   
This work was supported by the French National Research Agency (ANR-19-CE44-0005-01, PERIOMET project).     
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