1. Biochemistry and Chemical Biology
  2. Microbiology and Infectious Disease
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The NTP generating activity of pyruvate kinase II is critical for apicoplast maintenance in plasmodium falciparum

  1. Russell P Swift
  2. Krithika Rajaram
  3. Cyrianne Keutcha
  4. Hans B Liu
  5. Bobby Kwan
  6. Amanda Dziedzic
  7. Anne E Jedlicka
  8. Sean T Prigge  Is a corresponding author
  1. Johns Hopkins Bloomberg School of Public Health, United States
Research Article
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Cite this article as: eLife 2020;9:e50807 doi: 10.7554/eLife.50807

Abstract

The apicoplast of Plasmodium falciparum parasites is believed to rely on the import of three-carbon phosphate compounds for use in organelle anabolic pathways, in addition to the generation of energy and reducing power within the organelle. We generated a series of genetic deletions in an apicoplast metabolic bypass line to determine which genes involved in apicoplast carbon metabolism are required for blood-stage parasite survival and organelle maintenance. We found that pyruvate kinase II (PyrKII) is essential for organelle maintenance, but that production of pyruvate by PyrKII is not responsible for this phenomenon. Enzymatic characterization of PyrKII revealed activity against all NDPs and dNDPs tested, suggesting that it may be capable of generating a broad range of nucleotide triphosphates. Conditional mislocalization of PyrKII resulted in decreased transcript levels within the apicoplast that preceded organelle disruption, suggesting that PyrKII is required for organelle maintenance due to its role in nucleotide triphosphate generation.

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Author details

  1. Russell P Swift

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Krithika Rajaram

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4830-5471

  3. Cyrianne Keutcha

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Hans B Liu

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Bobby Kwan

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Amanda Dziedzic

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Anne E Jedlicka

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  8. Sean T Prigge

    Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    For correspondence
    sprigge@jhsph.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9684-1733

Funding

National Institute of Allergy and Infectious Diseases (R01AI065853)

  • Sean T Prigge

National Institute of Allergy and Infectious Diseases (R21AI101589)

  • Sean T Prigge

National Institute of General Medical Sciences (R25GM109441)

  • Cyrianne Keutcha

National Institute of Allergy and Infectious Diseases (T32AI007417)

  • Krithika Rajaram

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: August 2, 2019
  2. Accepted: August 20, 2020
  3. Accepted Manuscript published: August 20, 2020 (version 1)
  4. Version of Record published: September 10, 2020 (version 2)

Copyright

© 2020, Swift 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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