Activity of wild-type and mutant forms of C. elegans CCT. Shown is the activity of each enzyme in the presence of increasing concentration of PC:oleate vesicles. Concentrations, from left to right, are 0 μM, 2.5 μM, 5 μM, 10 μM, and 20 μM PC:oleate. 4Ser denotes a mutant enzyme where leucine 246, tryptophan 249, isoleucine 256, and isoleucine 257 were replaced simultaneously by serine. Experiments were repeated using similar lipid concentrations and different preparations of enzyme. Data are representative of the trends consistently observed.