Figure 5.

Structure–function relationship between PfATP4 mutations and compound treatment. Effects of (a) aminopyrazole and (b) spiroindolone inhibitors on intracellular sodium concentration [Na⁺]_i in the Dd2^EF1 and GNF-Pf4492R-1 strains. [Na⁺]_i traces for extracted trophozoite-stage parasites treated with saline or inhibitor immediately prior to fluorescence acquisition. Inhibitors were added at 1 × , 3×, 10×, or 100× the IC₅₀ for the Dd2^EF1 parent. Traces are representative of those obtained from a minimum of four independent experiments performed in duplicate. Calibration curves were generated for each strain and each experimental replicate to determine [Na⁺]_i.