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Record Information
Version3.6
Creation Date2009-03-24 16:22:04 UTC
Update Date2014-02-21 16:51:21 UTC
HMDB IDHMDB12082
Secondary Accession NumbersNone
Metabolite Identification
Common NameLysoSM(d18:0)
DescriptionSphingomyelin (d18:0/0:0) or LysoSM(d18:0) is a type of sphingolipid found in animal cell membranes, especially in the membranous myelin sheath which surrounds some nerve cell axons. It usually consists of phosphorylcholine and ceramide. In humans, sphingomyelin is the only membrane phospholipid not derived from glycerol. Like all sphingolipids, SPH has a ceramide core (sphingosine bonded to a fatty acid via an amide linkage). In addition it contains one polar head group, which is either phosphocholine or phosphoethanolamine. The plasma membrane of cells is highly enriched in sphingomyelin and is considered largely to be found in the exoplasmic leaflet of the cell membrane. However, there is some evidence that there may also be a sphingomyelin pool in the inner leaflet of the membrane. Moreover, neutral sphingomyelinase-2 - an enzyme that breaks down sphingomyelin into ceramide has been found to localise exclusively to the inner leaflet further suggesting that there may be sphingomyelin present there. Sphingomyelin can accumulate in a rare hereditary disease called Niemann-Pick Disease, types A and B. Niemann-Pick disease is a genetically-inherited disease caused by a deficiency in the enzyme Sphingomyelinase, which causes the accumulation of Sphingomyelin in spleen, liver, lungs, bone marrow, and the brain, causing irreversible neurological damage. SMs play a role in signal transduction. Sphingomyelins are synthesized by the transfer of phosphorylcholine from phosphatidylcholine to a ceramide in a reaction catalyzed by sphingomyelin synthase.
Structure
Thumb
Synonyms
  1. Lysosphingomyelin
  2. SM(d18:0/0:0)
  3. Sphinganine-1-phosphocholine
  4. Sphingomyelin(d18:0/0:0)
Chemical FormulaC23H51N2O5P
Average Molecular Weight466.6352
Monoisotopic Molecular Weight466.353559264
IUPAC Name(2-{[(2S,3R)-2-amino-3-hydroxyoctadecyl phosphonato]oxy}ethyl)trimethylazanium
Traditional IUPAC Name(2-{[(2S,3R)-2-amino-3-hydroxyoctadecyl phosphonato]oxy}ethyl)trimethylazanium
CAS Registry NumberNot Available
SMILES
CCCCCCCCCCCCCCC[C@@H](O)[C@@H](N)COP([O-])(=O)OCC[N+](C)(C)C
InChI Identifier
InChI=1S/C23H51N2O5P/c1-5-6-7-8-9-10-11-12-13-14-15-16-17-18-23(26)22(24)21-30-31(27,28)29-20-19-25(2,3)4/h22-23,26H,5-21,24H2,1-4H3/t22-,23+/m0/s1
InChI KeyGSEOJHIBPQRSNH-XZOQPEGZSA-N
Chemical Taxonomy
KingdomOrganic Compounds
Super ClassLipids
ClassSphingolipids
Sub ClassLysosphingomyelins and Lysoglycosphingolipids
Other Descriptors
  • Aliphatic Acyclic Compounds
  • Lysosphingomyelins and lysoglycosphingolipids(Lipidmaps)
Substituents
  • 1,2 Aminoalcohol
  • Choline
  • Organic Hypophosphite
  • Organic Phosphite
  • Phosphocholine
  • Phosphoethanolamine
  • Phosphoric Acid Ester
  • Primary Aliphatic Amine (Alkylamine)
  • Quaternary Ammonium Salt
  • Secondary Alcohol
Direct ParentLysosphingomyelins and Lysoglycosphingolipids
Ontology
StatusExpected and Not Quantified
Origin
  • Endogenous
  • Food
Biofunction
  • Cell signaling
  • Energy source
  • Fuel and energy storage
  • Fuel or energy source
  • Membrane component
  • Membrane integrity/stability
Application
  • Nutrients
  • Stabilizers
  • Surfactants and Emulsifiers
Cellular locations
  • Extracellular
  • Membrane
Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
PropertyValueSource
water solubility7.040E-04 g/LALOGPS
logP1.72ALOGPS
logP-0.047ChemAxon
logS-5.9ALOGPS
pKa (strongest acidic)1.83ChemAxon
pKa (strongest basic)9.73ChemAxon
physiological charge1ChemAxon
hydrogen acceptor count4ChemAxon
hydrogen donor count2ChemAxon
polar surface area104.84ChemAxon
rotatable bond count22ChemAxon
refractivity139.1ChemAxon
polarizability56.39ChemAxon
Spectra
SpectraNot Available
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane
Biofluid LocationsNot Available
Tissue LocationNot Available
PathwaysNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB028751
KNApSAcK IDNot Available
Chemspider ID21403135
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
NuGOwiki LinkHMDB12082
Metagene LinkHMDB12082
METLIN IDNot Available
PubChem Compound44260122
PDB IDNot Available
ChEBI IDNot Available
References
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General ReferencesNot Available

Enzymes

General function:
Involved in hydrolase activity
Specific function:
Converts sphingomyelin to ceramide. Also has phospholipase C activities toward 1,2-diacylglycerolphosphocholine and 1,2-diacylglycerolphosphoglycerol. Isoform 2 and isoform 3 have lost catalytic activity.
Gene Name:
SMPD1
Uniprot ID:
P17405
Molecular weight:
69935.53
General function:
Involved in galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase activity
Specific function:
Involved in the biosynthesis of L2/HNK-1 carbohydrate epitope on glycoproteins. Can also play a role in glycosaminoglycan biosynthesis. Substrates include asialo-orosomucoid (ASOR), asialo-fetuin, and asialo-neural cell adhesion molecule. Requires sphingomyelin for activity: stearoyl-sphingomyelin was the most effective, followed by palmitoyl-sphingomyelin and lignoceroyl-sphingomyelin. Activity was demonstrated only for sphingomyelin with a saturated fatty acid and not for that with an unsaturated fatty acid, regardless of the length of the acyl group (By similarity).
Gene Name:
B3GAT1
Uniprot ID:
Q9P2W7
Molecular weight:
38255.675
General function:
Involved in catalytic activity
Specific function:
Converts sphingomyelin to ceramide. Also has phospholipase C activity toward palmitoyl lyso-phosphocholine. Does not appear to have nucleotide pyrophosphatase activity.
Gene Name:
ENPP7
Uniprot ID:
Q6UWV6
Molecular weight:
51493.415
General function:
Involved in metal ion binding
Specific function:
Converts sphingomyelin to ceramide. Hydrolyze 1-acyl-2-lyso-sn-glycero-3-phosphocholine (lyso-PC) and 1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine (lyso-platelet-activating factor). The physiological substrate seems to be Lyso-PAF.
Gene Name:
SMPD2
Uniprot ID:
O60906
Molecular weight:
47645.29
General function:
Involved in lipid metabolic process
Specific function:
Saposin-D is a specific sphingomyelin phosphodiesterase activator (EC 3.1.4.12)
Gene Name:
PSAP
Uniprot ID:
P07602
Molecular weight:
58112.1
General function:
Involved in calcium ion binding
Specific function:
Hydrolyzes the phosphatidylinositol 4,5-bisphosphate (PIP2) to generate 2 second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). DAG mediates the activation of protein kinase C (PKC), while IP3 releases Ca(2+) from intracellular stores. Essential for trophoblast and placental development. May participate in cytokinesis by hydrolyzing PIP2 at the cleavage furrow.
Gene Name:
PLCD3
Uniprot ID:
Q8N3E9
Molecular weight:
89257.54
General function:
Involved in metal ion binding
Specific function:
Catalyzes the hydrolysis of sphingomyelin to form ceramide and phosphocholine. Ceramide mediates numerous cellular functions, such as apoptosis and growth arrest, and is capable of regulating these 2 cellular events independently. Also hydrolyzes sphingosylphosphocholine. Regulates the cell cycle by acting as a growth suppressor in confluent cells. Probably acts as a regulator of postnatal development and participates in bone and dentin mineralization.
Gene Name:
SMPD3
Uniprot ID:
Q9NY59
Molecular weight:
71080.1
General function:
Involved in metal ion binding
Specific function:
Catalyzes the hydrolysis of membrane sphingomyelin to form phosphorylcholine and ceramide.
Gene Name:
SMPD4
Uniprot ID:
Q9NXE4
Molecular weight:
86192.575
General function:
Involved in catalytic activity
Specific function:
Non-lysosomal glucosylceramidase that catalyzes the conversion of glucosylceramide to free glucose and ceramide. Involved in sphingomyelin generation and prevention of glycolipid accumulation. May also catalyze the hydrolysis of bile acid 3-O-glucosides, however, the relevance of such activity is unclear in vivo.
Gene Name:
GBA2
Uniprot ID:
Q9HCG7
Molecular weight:
104648.13
General function:
Involved in sphingomyelin biosynthetic process
Specific function:
Not Available
Gene Name:
SAMD8
Uniprot ID:
Q96LT4
Molecular weight:
48320.2