Serine C-palmitoyltransferase

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.

[1] 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.

Initially PLP cofactor is bound to the active-site lysine via a Schiff base to form the holo-form or internal aldimine of the enzyme.

[8] Specifically, the S. paucimobilis isoform features an active-site arginine residue (Arg378) that plays a key role in stabilizing the carboxy moiety of the PLP-L-serine external aldimine intermediate.

[9] Other homologues, such as in Sphingobacterium multivorum, feature the carboxy moiety bound to serine and methionine residues via water in place of arginine.

[12][13][14] HSAN1 (hereditary sensory and autonomic neuropathy type 1) is a genetic disorder caused by mutations in either one of SPTLC1 or SPTLC2, genes encoding the two heterodimeric subunits of the eukaryotic serine C-palmitoyltransferase enzyme.