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bioRxiv · 10.1101/2024.01.12.575445

Venturicidin A affects the mitochondrial membrane potential and induces kDNA loss in Trypanosoma brucei

Hauser, D. A.·Kaiser, M.·Mäser, P.·Albisetti, A.
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Abstract

Neglected tropical diseases caused by trypanosomatid parasites have devastating health and economic consequences, especially in tropical areas. New drugs or new combination therapies to fight these parasites are urgently needed. Venturicidin A, a macrolide extracted from Streptomyces, inhibits the ATP synthase complex of fungi and bacteria. However, its effect on trypanosomatids is not fully understood. In this study, we tested venturicidin A on a panel of trypanosomatid parasites using Alamar Blue assays and found it to be highly active against Trypanosoma brucei and Leishmania donovani, but much less so against Trypanosoma evansi. Using fluorescence microscopy we observed a rapid loss of the mitochondrial membrane potential in T. brucei bloodstream forms upon venturicidin A treatment. Additionally, we report the loss of the mitochondrial DNA in approximately 40 to 50% of the treated parasites. We conclude that venturicidin A targets the ATP synthase of T. brucei, and we suggest that this macrolide could be a candidate for antitrypanosomatid drug repurposing, drug combinations, or medicinal chemistry programs.

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Hauser, D. A., Kaiser, M., Mäser, P., Albisetti, A.. 2024-01-15. Venturicidin A affects the mitochondrial membrane potential and induces kDNA loss in Trypanosoma brucei. https://doi.org/10.1101/2024.01.12.575445

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