Figure 1. Glycolysis is the primary source of energy for Toxoplasma motility.

Toxoplasma tachyzoites were isolated from an infected monolayer 30–32 hours after infection as described in Materials and Methods. Parasites were collected by centrifugation and resuspended in EC buffer containing no carbon source or in the presence of glucose, glucose and KCN, or a mixture of pyruvate, lactate and glutamine. The effect of 10 nM atovaquone on Toxoplasma motility was analyzed in separate experiments. Incubations were performed in air or under a nitrogen atmosphere for 15 minutes at 37°C. Motility experiments were performed in quadruplicate and analyzed as described in Materials and Methods. The average fraction of motile parasites (±S.D.) under the different incubation conditions is shown.