The African trypanosome Trypanosoma brucei is a single-celled eukaryotic protozoan parasite with a single cilium/flagellum. It cycles between its mammalian host (bloodstream cell), in which it scavenges cholesterol, and its tsetse fly host (procyclic cell), in which it both scavenges cholesterol and synthesizes ergosterol. For the first part of the...