IUBMB Enzyme Nomenclature


Accepted name: sphingomyelin synthase

Reaction: a ceramide + a phosphatidylcholine = a sphingomyelin + a 1,2-diacyl-sn-glycerol

For diagram click here.

Glossary: sphingomyelin = a ceramide-1-phosphocholine
ceramide = an N-acylsphingoid. The fatty acids of naturally occurring ceramides range in chain length from about C16 to about C26 and may contain one or more double bonds and/or hydroxy substituents at C-2
sphingoid = sphinganine, i.e. D-erythro-2-aminooctadecane-1,3-diol, and its homologues and stereoisomers (see also Lip-1.4)

Other name(s): SM synthase; SMS1; SMS2

Systematic name: ceramide:phosphatidylcholine cholinephosphotransferase

Comments: The reaction can occur in both directions [3]. This enzyme occupies a central position in sphingolipid and glycerophospholipid metabolism [4]. Up- and down-regulation of its activity has been linked to mitogenic and pro-apoptotic signalling in a variety of mammalian cell types [4]. Unlike EC, ceramide cholinephosphotransferase, CDP-choline cannot replace phosphatidylcholine as the donor of the phosphocholine moiety of sphingomyelin [2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 58703-97-2


1. Ullman, M.D. and Radin, N.S. The enzymatic formation of sphingomyelin from ceramide and lecithin in mouse liver. J. Biol. Chem. 249 (1974) 1506-1512. [PMID: 4817756]

2. Voelker, D.R. and Kennedy, E.P. Cellular and enzymic synthesis of sphingomyelin. Biochemistry 21 (1982) 2753-2759. [PMID: 7093220]

3. Huitema, K., van den Dikkenberg, J., Brouwers, J.F. and Holthuis, J.C. Identification of a family of animal sphingomyelin synthases. EMBO J. 23 (2004) 33-44. [PMID: 14685263]

4. Tafesse, F.G., Ternes, P. and Holthuis, J.C. The multigenic sphingomyelin synthase family. J. Biol. Chem. 281 (2006) 29421-29425. [PMID: 16905542]

5. Yamaoka, S., Miyaji, M., Kitano, T., Umehara, H. and Okazaki, T. Expression cloning of a human cDNA restoring sphingomyelin synthesis and cell growth in sphingomyelin synthase-defective lymphoid cells. J. Biol. Chem. 279 (2004) 18688-18693. [PMID: 14976195]

[EC created 2006]

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