Myriocin is a atypical amino acid and an antibiotic with potent immunosuppressant activity. Studies suggest that the immunosuppressant activity in the cytotoxic T-cell line CTTL-2 is due to apoptosis induction. Myriocin very potent inhibitor of serine palmitoyltransferase and thus blocks the synthesis ceramide, a precursor in sphingomyelin and glycosphingolipid biosynthesis. As a result Myriocin is a useful biochemical research tool for depleting cells of sphingolipids.