Serine palmitoyltransferase

Serine palmitoyltransferase
Crystallographic structure of serine palmitoyltransferase from S. paucimobilis. The cofactor PLP is visible in the center.
Identifiers
Symbol	SPT1
PDB	2JG2
UniProt	Q93UV0
Other data
EC number	2.3.1.50

In enzymology, a serine C-palmitoyltransferase (EC 2.3.1.50) is an enzyme that catalyzes the chemical reaction:

Thus, the two substrates of this enzyme are palmitoyl-CoA and L-serine, whereas its 3 products are CoA, 3-dehydro-D-sphinganine, and CO₂. This reaction is a key step in the biosynthesis of sphingosine which is a precursor of many other sphingolipids.

This enzyme participates in sphingolipid metabolism. It employs one cofactor, pyridoxal phosphate.

This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is palmitoyl-CoA:L-serine C-palmitoyltransferase (decarboxylating). Other names in common use include:

Serine C-palmitoyltransferase is a member of the AOS (a-oxoamine synthase) family of PLP-dependent enzymes, which catalyse the condensation of amino acids and acyl-CoA thioester substrates. The human enzyme is a heterodimer consisting of two monomeric subunits known as long chain base 1 and 2 (LCB1/2) encoded by separate genes. The active site of LCB2 contains lysine and other key catalytic residues that are not present in LCB1, which does not participate in catalysis but is nevertheless required for the synthesis and stability of the enzyme.