A secretory multifunctional serine protease, DegP of Plasmodium falciparum, plays an important role in thermo-oxidative stress, parasite growth and development

FEBS J. 2014 Mar;281(6):1679-99. doi: 10.1111/febs.12732. Epub 2014 Feb 24.


Plasmodium falciparum heat shock proteins and proteases are known for their indispensable roles in parasite virulence and survival in the host cell. They neutralize various host-derived stress responses that are deleterious for parasite growth and invasion. We report identification and functional characterization of the first DegP from an apicomplexan (P. falciparum). To determine the molecular identity and functions of the parasite-encoded DegP, we complemented the Escherichia coli degP null mutant with a putative PfdegP gene, and the results showed that PfDegP complements the growth defect of the temperature sensitive DegP-deficient mutant and imparts resistance to non-permissive temperatures and oxidative stress. Molecular interaction studies showed that PfDegP exists as a complex with parasite-encoded heat shock protein 70, iron superoxide dismutase and enolase. DegP expression is significantly induced in parasite culture upon heat shock/oxidative stress. Our data suggest that the PfDegP protein may play a role in the growth and development of P. falciparum through its ability to confer protection against thermal/oxidative stress. Antibody against DegP showed anti-plasmodial activity against blood-stage parasites in vitro, suggesting that PfDegP and its associated complex may be a potential focus for new anti-malarial therapies.

Structured digital abstract: ●PfDegP physically interacts with PfHsp70 and PfEno by anti-bait co-immunoprecipitation (View interaction) ●PfDegP physically interacts with PfEno, PfSod, PfOat, PfHsp70, PfLDH and PfGpi by anti-bait co-immunoprecipitation (View interaction) ●PfHsp-70 and PfDegP co-localize by fluorescence microscopy (View interaction) ●PfDegP physically interacts with PfOat, PfHsp70, PfEno, PfSod, PfGpi and PfLDH by surface plasmon resonance (View interaction) ●PfEno and PfDegP co-localize by fluorescence microscopy (View interaction) ●PfDegP and PfHsp70 co-localize by co-sedimentation through density gradient (View interaction).

Keywords: DegP; Plasmodium falciparum; heat shock proteins; molecular chaperone; stress responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism
  • Genes, Protozoan
  • Genetic Complementation Test
  • HSP70 Heat-Shock Proteins / chemistry
  • HSP70 Heat-Shock Proteins / metabolism
  • Heat-Shock Proteins / chemistry
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism*
  • Heat-Shock Response
  • Molecular Sequence Data
  • Multiprotein Complexes / chemistry
  • Multiprotein Complexes / metabolism
  • Oxidative Stress
  • Periplasmic Proteins / chemistry
  • Periplasmic Proteins / genetics
  • Periplasmic Proteins / metabolism*
  • Phosphopyruvate Hydratase / chemistry
  • Phosphopyruvate Hydratase / metabolism
  • Phylogeny
  • Plasmodium falciparum / enzymology*
  • Plasmodium falciparum / genetics
  • Plasmodium falciparum / growth & development
  • Protein Structure, Quaternary
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Serine Endopeptidases / chemistry
  • Serine Endopeptidases / genetics
  • Serine Endopeptidases / metabolism*
  • Superoxide Dismutase / chemistry
  • Superoxide Dismutase / metabolism


  • Escherichia coli Proteins
  • HSP70 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Multiprotein Complexes
  • Periplasmic Proteins
  • Protozoan Proteins
  • Recombinant Proteins
  • Superoxide Dismutase
  • DegP protease
  • Serine Endopeptidases
  • Phosphopyruvate Hydratase