Abstract
The reactivity of sphingosine bases as substrates in the enzymatic synthesis of ceramide was in decreasing order of erythro-4-sphingenine, erythro-sphinganine, threo-4-sphingenine and threo-sphinganine in the microsomal fraction obtained from chicken liver. Unsaturated base-containing ceramide was enzymatically formed from 4-sphingenine and saturated basecontaining ceramide from sphinganine. The formation of unsaturated base-containing ceramide proceeded similar to that of saturated base-containing ceramide. The data explain in part, the fact that 4-sphingenine is generally superior to sphinganine as the constituent sphingosine base in sphingolipids, the biochemical derivatives of ceramide.