Bidirectional lipid inositolphosphotransferase capable of converting phosphatidylinositol (PI) and ceramide to inositol-phosphorylceramide (IPC) and diacylglycerol (DAG) and vice versa. Direction is dependent on the relative concentrations of DAG and ceramide as phosphoinositol acceptors. Essential for viability of the pathogenic bloodstream stage of this human protozoan parasite and, consequently, can be considered as potential drug target. Found only in procyclic parasites. Elevated ceramide levels and growth arrest; cells were arrested in division but replication of DNA and organelles continued giving rise to cells containing multiple nuclei, kinetoplasts and flagella. Belongs to the sphingomyelin synthase family.