Mg2+ Homeostasis Crucial for Salmonella Pathogenesis

Strategic Insights -

Researchers in the United States have highlighted the significance of Mg2+ homeostasis in Salmonella pathogenesis. A study published in the Proceedings of the National Academy of Sciences of the United States of America revealed that the increased expression of Mg2+ transport proteins enhances the survival of Salmonella enterica at high temperatures. The researchers isolated a mutation, chr-1, which increases the resistance of exponential phase cells to high temperature, and found that it results in high-level constitutive expression of the mgtA gene, which encodes a Mg2+ transporter.

Key Takeaways:

  • The transcription of the mgtA gene, which encodes a Mg2+ transporter, is regulated by a Mg2+-sensing riboswitch in Salmonella enterica.
  • The chr-1 mutation, a single base change in the mgtA riboswitch, causes high-level constitutive expression of mgtA and increases the resistance of exponential phase cells to high temperature.
  • The increased expression of the heterologous MgtE Mg2+ transport protein of Bacillus subtilis enhances the thermotolerance of S. enterica.
  • The researchers hypothesize that increased Mg2+ accumulation might enhance thermotolerance by protecting the integrity of proteins or membranes, mitigating oxidative damage, or acting as an inducer of thermoprotective functions.
  • K. Oconnor and colleagues found that high-level expression of mgtA results in increased cytosolic free Mg2+ concentration.
  • The study was published in the Proceedings of the National Academy of Sciences of the United States of America in 2009 (Oconnor et al., 2009).

Statistics:

  • 71-84: The page numbers of the paper by Cromie MJ, Shi Y, Latifi T, and Groisman EA (2006).
  • >17522-17527: The page numbers of the paper by K. Oconnor and colleagues (2009).
  • 106(41): The volume and issue number of the paper by K. Oconnor and colleagues (2009).
  • 2101 Constitution Avenue NW: The address of the National Academy of Sciences in Washington, DC.
  • 20418: The zip code of the National Academy of Sciences in Washington, DC.

Sources:

  • Cromie MJ, Shi Y, Latifi T, Groisman EA (2006) Cell 125: 71-84.
  • Oconnor, K., et al. (2009) Increased expression of Mg2+ transport proteins enhances the survival of Salmonella enterica at high temperature. Proceedings of the National Academy of Sciences of the United States of America, 106(41), 17522-17527.
  • National Acad Sciences, 2101 Constitution Avenue NW, Washington, DC 20418, USA.