Plasmodiumfalciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity

Flore Nardella¹, Tiantian Jiang², Lushun Wang³, Monica J Bohmer¹, Subhoja Chakraborty¹, John Okombo⁴, Jaeson Calla², Tatiane Macedo Silva⁵, Samuel Pazicky⁶, Jianwei Che⁷, Jin Jeon⁴, Evie Vincent¹, Nonlawat Boonyalai⁸, Rachael Coyle⁸, Mairi J Buchanan⁸, Samuel Schaefer², Daisy Chen², Amaan Khan², Emily Mayville⁴, Mariana Laureano De Souza², Mayland Treat⁹, Jordan Charlton¹⁰, Patrick K Tumwebaze¹¹, Seth Tjia⁶, Lukas Montejo¹, Karen Cover¹, Philip J Rosenthal¹², Roland A Cooper¹⁰, Zbynek Bozdech⁶, Marcus C S Lee⁸, Ratna Chakrabarti¹, Sanjay A Desai⁵, David A Fidock⁴, Jinhua Wang⁷, Nathanael S Gray¹³, Elizabeth A Winzeler¹⁴, Debopam Chakrabarti¹⁵

Affiliations

¹ Division of Molecular Microbiology, Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32826, USA.
² School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences, University California, San Diego, La Jolla, CA 92093, USA.
³ Department of Chemical and Systems Biology, ChEM-H, Stanford Cancer Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA.
⁴ Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY 10032, USA; Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA.
⁵ Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
⁶ School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
⁷ Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
⁸ Biological Chemistry and Drug Discovery, Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee, UK.
⁹ School of Public Health, University of California, Berkeley CA 94704, USA.
¹⁰ Department of Natural Sciences and Mathematics, Dominican University of California, San Rafael, CA 94901, USA.
¹¹ Infectious Disease Research Collaboration, Kampala, Uganda.
¹² Department of Medicine, University of California, San Francisco, CA 94110, USA.
¹³ Department of Chemical and Systems Biology, ChEM-H, Stanford Cancer Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA. Electronic address: nsgray01@stanford.edu.
¹⁴ School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences, University California, San Diego, La Jolla, CA 92093, USA. Electronic address: ewinzeler@health.ucsd.edu.
¹⁵ Division of Molecular Microbiology, Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32826, USA. Electronic address: dchak@ucf.edu.

PMID: 40628257
PMCID: PMC12406260 (available on 2026-07-07)
DOI: 10.1016/j.chembiol.2025.06.003

Plasmodiumfalciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity

Flore Nardella et al. Cell Chem Biol. 2025.

. 2025 Jul 17;32(7):926-941.e23.

doi: 10.1016/j.chembiol.2025.06.003. Epub 2025 Jul 7.

Authors

Affiliations

¹ Division of Molecular Microbiology, Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32826, USA.
² School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences, University California, San Diego, La Jolla, CA 92093, USA.
³ Department of Chemical and Systems Biology, ChEM-H, Stanford Cancer Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA.
⁴ Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY 10032, USA; Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA.
⁵ Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
⁶ School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
⁷ Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
⁸ Biological Chemistry and Drug Discovery, Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee, UK.
⁹ School of Public Health, University of California, Berkeley CA 94704, USA.
¹⁰ Department of Natural Sciences and Mathematics, Dominican University of California, San Rafael, CA 94901, USA.
¹¹ Infectious Disease Research Collaboration, Kampala, Uganda.
¹² Department of Medicine, University of California, San Francisco, CA 94110, USA.
¹³ Department of Chemical and Systems Biology, ChEM-H, Stanford Cancer Institute, School of Medicine, Stanford University, Stanford, CA 94305, USA. Electronic address: nsgray01@stanford.edu.
¹⁴ School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences, University California, San Diego, La Jolla, CA 92093, USA. Electronic address: ewinzeler@health.ucsd.edu.
¹⁵ Division of Molecular Microbiology, Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32826, USA. Electronic address: dchak@ucf.edu.

PMID: 40628257
PMCID: PMC12406260 (available on 2026-07-07)
DOI: 10.1016/j.chembiol.2025.06.003

Abstract

Kinase inhibitors are potent therapeutics, but most essential Plasmodium kinases remain unexploited as antimalarial targets. We identified compound 12, a type II kinase inhibitor based on aminopyridine and 2,6-benzimidazole scaffolds, as a lead compound with nanomolar potency, fast action, and in vivo activity in the Plasmodium berghei rodent malaria model. Three-hybrid luciferase fragment complementation, enzymatic studies, and cellular thermal shift assays implicated Plasmodium protein kinase 6 (PfPK6) as the target. However, conditional knockdown of PfPK6 did not alter 12 potency, suggesting complex mechanisms of action. In vitro selection for compound 12 resistance revealed mutations in three transporters: multidrug-resistance protein 1, chloroquine resistance transporter and V-type ATPase, indicating a digestive vacuole site of action. Compound 12 inhibited β-hematin and hemozoin formation while increasing free heme levels, suggesting antimalarial activity via blockade of heme detoxification. Our studies repurpose a safe human kinase inhibitor as a potent, fast-acting antimalarial with established in vivo efficacy.

Keywords: P. falciparum chloroquine resistance transporter; P. falciparum protein kinase 6; PfCRT; PfPK6; Plasmodium; hemozoin formation; malaria; type-II kinase inhibitor.

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Conflict of interest statement

Declaration of interests Intellectual property disclosure for compound 12 (YLIU-06-026-1) has been filed under WO 2024/196989 A1 dated 26 September 2024. N.G. is a founder, science advisory board member (SAB), and equity holder in Syros, C4, Allorion, Lighthorse, Voronoi, Inception, Matchpoint, CobroVentures, GSK, Larkspur (board member), Shenandoah (board member) and Soltego (board member). The Gray lab receives or has received research funding from Novartis, Takeda, Astellas, Taiho, Jansen, Kinogen, Arbella, Deerfield, Springworks, Interline and Sanofi. J.W. is a consultant and equity holder for Soltego. J.C. is a cofounder of Matchpoint therapeutics and consultant for Soltego, Allorion and Matchpoint Therapeutics, and holds equity in Soltego, Allorion, Matchpoint and M3 Bioinformatics & Technology Inc. N.G. is a member of the Cell Chemical Biology advisory board.

References

1. WHO (2024). World malaria report 2024.
1. Rosenthal PJ, Asua V, and Conrad MD (2024). Emergence, transmission dynamics and mechanisms of artemisinin partial resistance in malaria parasites in Africa. Nat Rev Microbiol 22, 373–384. 10.1038/s41579-024-01008-2. - DOI - PubMed
1. Roskoski R Jr. (2024). Properties of FDA-approved small molecule protein kinase inhibitors: A 2024 update. Pharmacol Res 200, 107059. 10.1016/j.phrs.2024.107059. - DOI - PubMed
1. Liu Y, and Gray NS (2006). Rational design of inhibitors that bind to inactive kinase conformations. Nat Chem Biol 2, 358–364. 10.1038/nchembio799. - DOI - PubMed
1. Wang L, Bohmer MJ, Wang J, Nardella F, Calla J, Laureano De Souza M, Schindler KA, Montejo L, Mittal N, Rocamora F, Treat M, Charlton JT, Tumwebaze PK, Rosenthal PJ, Cooper RA, Chakrabarti R, Winzeler EA, Chakrabarti D, and Gray NS (2024). Discovery of Potent Antimalarial Type II Kinase Inhibitors with Selectivity over Human Kinases. Journal of medicinal chemistry 67, 1460–1480. 10.1021/acs.jmedchem.3c02046. - DOI - PMC - PubMed

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Plasmodiumfalciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity

Affiliations

Plasmodiumfalciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity

Authors

Affiliations

Abstract

Conflict of interest statement

References

MeSH terms

Substances

Grants and funding

LinkOut - more resources

Full Text Sources

Research Materials