1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics
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The magnesium transporter A is activated by cardiolipin and is highly sensitive to free magnesium in vitro

  1. Saranya Subramani
  2. Harmonie Perdreau-Dahl
  3. Jens Preben Morth  Is a corresponding author
  1. Nordic EMBL Partnership University of Oslo, Norway
Research Article
  • Cited 20
  • Views 3,553
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Cite this article as: eLife 2016;5:e11407 doi: 10.7554/eLife.11407

Abstract

The magnesium transporter A (MgtA) is a specialized P-type ATPase, believed to import Mg2+ into the cytoplasm. In Salmonella typhimurium and Escherichia coli, the virulence determining two-component system PhoQ/PhoP regulates the transcription of mgtA gene by sensing Mg2+ concentrations in the periplasm. However, the factors that affect MgtA function are not known. This study demonstrates, for the first time, that MgtA is highly dependent on anionic phospholipids and in particular, cardiolipin. Colocalization studies confirm that MgtA is found in the cardiolipin lipid rafts in the membrane. We further show that MgtA is highly sensitive to free Mg2+ (Mg2+free) levels in the solution. MgtA is activated when the Mg2+free concentration is reduced below 10 μM and is strongly inhibited above 1 mM, indicating that Mg2+free acts as product inhibitor. Combined, our findings conclude that MgtA may act as a sensor as well as a transporter of Mg2+.

Article and author information

Author details

  1. Saranya Subramani

    Norwegian Centre of Molecular Medicine, Nordic EMBL Partnership University of Oslo, Oslo, Norway
    Competing interests
    The authors declare that no competing interests exist.
  2. Harmonie Perdreau-Dahl

    Norwegian Centre of Molecular Medicine, Nordic EMBL Partnership University of Oslo, Oslo, Norway
    Competing interests
    The authors declare that no competing interests exist.
  3. Jens Preben Morth

    Norwegian Centre of Molecular Medicine, Nordic EMBL Partnership University of Oslo, Oslo, Norway
    For correspondence
    j.p.morth@ncmm.uio.no
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Eduardo A Groisman, Yale University/HHMI, United States

Publication history

  1. Received: September 5, 2015
  2. Accepted: January 16, 2016
  3. Accepted Manuscript published: January 18, 2016 (version 1)
  4. Version of Record published: February 7, 2016 (version 2)
  5. Version of Record updated: February 14, 2017 (version 3)

Copyright

© 2016, Subramani et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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