Notes: 3-keto Sphinganine (d18:0) is an intermediate in the biosynthesis of C18 ceramide (d18:1/18:0) (Item No. 19556).{36079} It is a lyso-sphingolipid formed by the condensation of L-serine and palmitoyl-CoA by serine palmitoyl transferase (SPT). Vitamin K deficiency inactivates SPT resulting in a decrease in the production of 3-keto sphinganine (d18:0) and other sphingolipids.{12347} [Matreya, LLC. Catalog No. 1876]