摘要:SummaryBoron-containing compounds represent a promising class of molecules with proven efficacy against a wide range of pathogens, including apicomplexan parasites. Following lead optimization, the benzoxaborole AN13762 was identified as a preclinical candidate against the human malaria parasite, yet the molecular target remained uncertain. Here, we uncovered the parasiticidal mechanisms of AN13762, by combining forward genetics with transcriptome sequencing and computational mutation discovery and usingToxoplasma gondiias a relevant model for Apicomplexa. AN13762 was shown to targetTgCPSF3, the catalytic subunit of the pre-mRNA cleavage and polyadenylation complex, as the anti-pan-apicomplexan benzoxaborole compound, AN3661. However, unique mutations within theTgCPSF3 catalytic site conferring resistance to AN13762 do not confer cross-protection against AN3661, suggesting a divergent resistance mechanism. Finally, in agreement with the high sequence conservation of CPSF3 betweenToxoplasmaandCryptosporidium, AN13762 shows oral efficacy in cryptosporidiosis mouse model, a disease for which new drug development is of high priority.Graphical AbstractDisplay OmittedHighlights•AN13762 is active againstT. gondiiparasites•Parasites resistant to AN13762 harbor mutations withinTgCPSF3•Mutations withinTgCPSF3 confer resistance to AN13762•AN13762 offers an alternative for targeting CPSF3 inToxoplasmaandCryptosporidiumMolecular Biology; Molecular Medicine; Microbiology; Microbiology Parasite