Effect of the depletion of intracellular ATP on NBD-PC internalization.^a

aInternalization of NBD-PC in cultured log-phase promastigotes at 2°C was analyzed by flow cytometry using back-exchange to BSA. The internalization rates were calculated by fitting the data to a single-exponential equation as described in Materials and Methods. bATP depletion was performed by pretreating parasites with 5 mM 2-deoxyglucose and 5 µg/mL oligomycin for 30 min at 25°C. cResults are expressed relative to the NBD-PC internalization rate of untreated cells and are shown as the mean ± SD of three independent experiments.