Abstract

Trypanosomes have a trypanothione redox metabolism that provides the reducing equivalents for numerous essential processes, most being mediated by tryparedoxin (Tpx). While the biosynthesis and reduction of trypanothione are cytosolic, the molecular basis of the thiol redox homeostasis in the single mitochondrion of these parasites has remained largely unknown. Here we expressed Tpx-roGFP2, roGFP2-hGrx1 or roGFP2 in either the cytosol or mitochondrion of Trypanosoma brucei. We show that the novel Tpx-roGFP2 is a superior probe for the trypanothione redox couple and that the mitochondrial matrix harbors a trypanothione system. Inhibition of trypanothione biosynthesis by the anti-trypanosomal drug Eflornithine impairs the ability of the cytosol and mitochondrion to cope with exogenous oxidative stresses, indicating a direct link between both thiol systems. Tpx depletion abolishes the cytosolic, but only partially affects the mitochondrial sensor response to H2O2. This strongly suggests that the mitochondrion harbors some Tpx and, another, as yet unidentified, oxidoreductase.

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All data generated or analysed during this study are included in the manuscript and supporting files.

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Author details

  1. Samantha Ebersoll

    Biochemie-Zentrum (BZH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Marta Bogacz

    Biochemie-Zentrum (BZH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Lina M Günter

    Biochemie-Zentrum (BZH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Tobias P Dick

    Biochemie-Zentrum (BZH), Universität Heidelberg, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. R Luise Krauth-Siegel

    Biochemie-Zentrum (BZH), Universität Heidelberg, Heidelberg, Germany
    For correspondence
    luise.krauth-siegel@bzh.uni-heidelberg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2164-8116

Funding

Deutsche Forschungsgemeinschaft (Kr1242/8-1)

  • R Luise Krauth-Siegel

Deutsche Forschungsgemeinschaft (SPP 1710 Kr1242/6-2)

  • R Luise Krauth-Siegel

Deutsche Forschungsgemeinschaft (SPP 1710 Di731/3-2)

  • Tobias P Dick

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2020, Ebersoll 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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  1. Samantha Ebersoll
  2. Marta Bogacz
  3. Lina M Günter
  4. Tobias P Dick
  5. R Luise Krauth-Siegel
(2020)
A tryparedoxin-coupled biosensor reveals a mitochondrial trypanothione metabolism in trypanosomes
eLife 9:e53227.
https://doi.org/10.7554/eLife.53227

Share this article

https://doi.org/10.7554/eLife.53227

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