Fungal derived deoxaphomines target Plasmodium falciparum segregation through inhibition of PfActin1

Methyldeoxaphomin NPDG F is an analog of a natural product scaffold isolated from the fungi Trichocladium asperum. To identify the drug target, we performed in vitro evolution using the Dd2-Pol-delta hypermutator line and obtained three independent populations of parasites resistant to methyldeoxaphomin NPDG F. Whole genome sequencing using Illumina NovaSeq X Plus was performed on eight clones isolated from the three resistant flasks as well as the parent Dd2-Pol-delta parent line. Of 29 missense mutations found in the core genome of resistant clones, 4 were found in pfactin1. A molecular docking study with PfActin1 found that methyldeoxaphomin NPDG F occupies the same binding pocket as cytochalasin D. Resistant parasites were found to be cross resistant to cytochalasin D (but not actin stabilizer Jasplakinolide), suggesting NPDG F displays a similar mode of action and interaction with PfActin1.