Using unbiased chemical proteomics approaches to explore the target landscape of the resistance refractory 7-azaindole MMV022224 in Plasmodium falciparum

TY - JOUR

T1 - Using unbiased chemical proteomics approaches to explore the target landscape of the resistance refractory 7-azaindole MMV022224 in Plasmodium falciparum

AU - Syed, Aisha J.

AU - Milne, Rachel

AU - Corpas Lopez, Victoriano

AU - Dey, Gourav

AU - Boonyalai, Nonlawat

AU - Walls, Richard J

AU - Wiedemar, Natalie

AU - Montejo, Lukas

AU - Nardella, Flore

AU - Wicht, Kathryn J.

AU - Pasaje, Charisse Flerida A.

AU - Okombo, John

AU - Niles, Jacquin C.

AU - Fidock, David A.

AU - Lee, Marcus C. S.

AU - Chakrabarti, Debopam

AU - Patterson, Stephen

AU - Wyllie, Susan

PY - 2026/6/25

Y1 - 2026/6/25

N2 - Current standard of care artemisinin-based therapies for malaria are threatened by emerging drug resistance. Developing antimalarials with novel mechanisms of action and low propensity for resistance is of the highest priority. Here, we explore the target landscape of MMV022224, a promising anti-malarial that is active against multiple stages of Plasmodium falciparum and refractory to resistance generation. Using two orthogonal chemical proteomics approaches, chemical pulldown and thermal proteome profiling, we demonstrate that MMV022224 binds selectively and with high affinity to the genetically essential P. falciparum protein kinase 6 (PfPK6), as well as to several additional Plasmodium kinases. Enzymatic studies verify that MMV022224 inhibits PfPK6, however, PfPK6 knockdown does not affect parasite compound susceptibility, confirming that PfPK6 inhibition is not the sole driver of antimalarial activity and that MMV022224 may act through broader, kinase focused polypharmacology. Employing the same chemical proteomics strategies, we demonstrate that the structurally related azaindole, TCMDC-135051, is a selective inhibitor of the cyclin-dependent kinase PfCLK3. Collectively, these studies demonstrate the value of chemical proteomics for antimalarial drug target deconvolution.

AB - Current standard of care artemisinin-based therapies for malaria are threatened by emerging drug resistance. Developing antimalarials with novel mechanisms of action and low propensity for resistance is of the highest priority. Here, we explore the target landscape of MMV022224, a promising anti-malarial that is active against multiple stages of Plasmodium falciparum and refractory to resistance generation. Using two orthogonal chemical proteomics approaches, chemical pulldown and thermal proteome profiling, we demonstrate that MMV022224 binds selectively and with high affinity to the genetically essential P. falciparum protein kinase 6 (PfPK6), as well as to several additional Plasmodium kinases. Enzymatic studies verify that MMV022224 inhibits PfPK6, however, PfPK6 knockdown does not affect parasite compound susceptibility, confirming that PfPK6 inhibition is not the sole driver of antimalarial activity and that MMV022224 may act through broader, kinase focused polypharmacology. Employing the same chemical proteomics strategies, we demonstrate that the structurally related azaindole, TCMDC-135051, is a selective inhibitor of the cyclin-dependent kinase PfCLK3. Collectively, these studies demonstrate the value of chemical proteomics for antimalarial drug target deconvolution.

KW - Chemical pulldown

KW - Plasmodium

KW - Chemical biology

KW - Isothermal TPP

KW - Target deconvolution

KW - Antimalarial Drug Discovery

U2 - 10.1021/acsinfecdis.6c00276

DO - 10.1021/acsinfecdis.6c00276

M3 - Article

SN - 2373-8227

JO - ACS Infectious Diseases

JF - ACS Infectious Diseases

ER -