Biochemical Screening of Five Protein Kinases from Plasmodium falciparum against 14,000 Cell-Active Compounds

PLoS One. 2016 Mar 2;11(3):e0149996. doi: 10.1371/journal.pone.0149996. eCollection 2016.


In 2010 the identities of thousands of anti-Plasmodium compounds were released publicly to facilitate malaria drug development. Understanding these compounds' mechanisms of action--i.e., the specific molecular targets by which they kill the parasite--would further facilitate the drug development process. Given that kinases are promising anti-malaria targets, we screened ~14,000 cell-active compounds for activity against five different protein kinases. Collections of cell-active compounds from GlaxoSmithKline (the ~13,000-compound Tres Cantos Antimalarial Set, or TCAMS), St. Jude Children's Research Hospital (260 compounds), and the Medicines for Malaria Venture (the 400-compound Malaria Box) were screened in biochemical assays of Plasmodium falciparum calcium-dependent protein kinases 1 and 4 (CDPK1 and CDPK4), mitogen-associated protein kinase 2 (MAPK2/MAP2), protein kinase 6 (PK6), and protein kinase 7 (PK7). Novel potent inhibitors (IC50 < 1 μM) were discovered for three of the kinases: CDPK1, CDPK4, and PK6. The PK6 inhibitors are the most potent yet discovered for this enzyme and deserve further scrutiny. Additionally, kinome-wide competition assays revealed a compound that inhibits CDPK4 with few effects on ~150 human kinases, and several related compounds that inhibit CDPK1 and CDPK4 yet have limited cytotoxicity to human (HepG2) cells. Our data suggest that inhibiting multiple Plasmodium kinase targets without harming human cells is challenging but feasible.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimalarials / pharmacology*
  • Calcium / metabolism
  • Cell Line, Tumor
  • Hep G2 Cells
  • Humans
  • Malaria, Falciparum / drug therapy
  • Malaria, Falciparum / metabolism
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase Kinases / metabolism
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / metabolism*
  • Protein Kinase Inhibitors / pharmacology
  • Protein Kinases / metabolism*
  • Protein Serine-Threonine Kinases / metabolism
  • Protozoan Proteins / metabolism


  • Antimalarials
  • Protein Kinase Inhibitors
  • Protozoan Proteins
  • Protein Kinases
  • protein kinase PK60
  • PK7 protein, Plasmodium falciparum
  • Protein Serine-Threonine Kinases
  • calcium-dependent protein kinase-1, Plasmodium falciparum
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase Kinases
  • Calcium