FIG. 6.

Kinetics of choline uptake into free parasites of B. divergens and inhibition by T16. (A) SLO-freed parasites were incubated for 10 min at 37°C into special RPMI with [¹⁴C]choline (6.72 to 50.4 nCi/nmol) (2.10⁷ cells in a final volume of 200 μl) and then isolated using a dibutylphthalate/dioctylphthalate oil cushion. Kinetics parameters were means of four independent experiments, each conducted in duplicate. Data shown are from a typical experiment fitted by nonlinear regression analysis for a Michaelis-Menten plot and by linear regression for a Lineweaver-Burke plot. (B) Concentration-dependent inhibition of choline uptake by T16. T16 compound was preincubated with free parasites for 5 min before the addition of 15 μM [¹⁴C]choline over 10 min at 37°C. Data are means ± standard errors of the means from three individual experiments, each in duplicate.