Elucidating the mitochondrial proteome of Toxoplasma gondii reveals the presence of a divergent cytochrome c oxidase

  1. Azadeh Seidi
  2. Linden S Muellner-Wong
  3. Esther Rajendran
  4. Edwin T Tjhin
  5. Laura Dagley
  6. Vincent YT Aw
  7. Pierre Faou
  8. Andrew I Webb
  9. Christopher J Tonkin
  10. Giel G van Dooren  Is a corresponding author
  1. Australian National University, Australia
  2. The Walter and Eliza Hall Institute of Medical Research, Australia
  3. La Trobe University, Australia

Abstract

The mitochondrion of apicomplexan parasites is critical for parasite survival, although the full complement of proteins that localize to this organelle has not been defined. Here we undertake two independent approaches to elucidate the mitochondrial proteome of the apicomplexan Toxoplasma gondii. We identify approximately 400 mitochondrial proteins, many of which lack homologs in the animals that these parasites infect, and most of which are important for parasite growth. We demonstrate that one such protein, termed TgApiCox25, is an important component of the parasite cytochrome c oxidase (COX) complex. We identify numerous other apicomplexan-specific components of COX, and conclude that apicomplexan COX, and apicomplexan mitochondria more generally, differ substantially in their protein composition from the hosts they infect. Our study highlights the diversity that exists in mitochondrial proteomes across the eukaryotic domain of life, and provides a foundation for defining unique aspects of mitochondrial biology in an important phylum of parasites.

Data availability

Mitochondrial proteomics data is available in on the ToxoDB website (http://toxodb.org).

The following data sets were generated

Article and author information

Author details

  1. Azadeh Seidi

    Research School of Biology, Australian National University, Canberra, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Linden S Muellner-Wong

    Research School of Biology, Australian National University, Canberra, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0348-6408
  3. Esther Rajendran

    Research School of Biology, Australian National University, Canberra, Australia
    Competing interests
    The authors declare that no competing interests exist.
  4. Edwin T Tjhin

    Research School of Biology, Australian National University, Canberra, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. Laura Dagley

    The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
    Competing interests
    The authors declare that no competing interests exist.
  6. Vincent YT Aw

    Research School of Biology, Australian National University, Canberra, Australia
    Competing interests
    The authors declare that no competing interests exist.
  7. Pierre Faou

    Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  8. Andrew I Webb

    The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
    Competing interests
    The authors declare that no competing interests exist.
  9. Christopher J Tonkin

    The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
    Competing interests
    The authors declare that no competing interests exist.
  10. Giel G van Dooren

    Research School of Biology, Australian National University, Canberra, Australia
    For correspondence
    giel.vandooren@anu.edu.au
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2455-9821

Funding

Australian Research Council (DP110103144)

  • Giel G van Dooren

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

Reviewing Editor

  1. Dominique Soldati-Favre, University of Geneva, Switzerland

Publication history

  1. Received: May 6, 2018
  2. Accepted: September 9, 2018
  3. Accepted Manuscript published: September 11, 2018 (version 1)
  4. Version of Record published: September 25, 2018 (version 2)

Copyright

© 2018, Seidi 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. Azadeh Seidi
  2. Linden S Muellner-Wong
  3. Esther Rajendran
  4. Edwin T Tjhin
  5. Laura Dagley
  6. Vincent YT Aw
  7. Pierre Faou
  8. Andrew I Webb
  9. Christopher J Tonkin
  10. Giel G van Dooren
(2018)
Elucidating the mitochondrial proteome of Toxoplasma gondii reveals the presence of a divergent cytochrome c oxidase
eLife 7:e38131.
https://doi.org/10.7554/eLife.38131

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