Cloning and characterization of a cDNA encoding serine palmitoyltransferase in Arabidopsis thaliana

The first and committed step in de novo sphingolipid synthesis is catalysed by serine palmitoyltransferase (EC 2.3.1.50), which condenses serine and palmitoyl-CoA to form 3-ketosphinganine in a pyridoxal-5'-phosphate-dependent reaction. We have isolated and characterized a cDNA clone from Arabidopsis thaliana that is homologous to yeast and mammalian LCB2. For a functional identification, the A. thaliana homologous cDNA was expressed in Escherichia coli, which resulted in significant production of new sphinganine in E. coli cells.