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Record Information
Version4.0
StatusDetected and Quantified
Creation Date2008-09-12 01:59:39 UTC
Update Date2017-12-13 16:45:13 UTC
HMDB IDHMDB0009781
Secondary Accession Numbers
  • HMDB09781
Metabolite Identification
Common NamePI(16:0/18:0)
DescriptionPI(16:0/18:0) is a phosphatidylinositol. Phosphatidylinositols are important lipids, both as a key membrane constituent and as a participant in essential metabolic processes, both directly and via a number of metabolites. Phosphatidylinositols are acidic (anionic) phospholipids that consist of a phosphatidic acid backbone, linked via the phosphate group to inositol (hexahydroxycyclohexane). Phosphatidylinositols can have many different combinations of fatty acids of varying lengths and saturation attached at the C-1 and C-2 positions. Fatty acids containing 18 and 20 carbons are the most common. PI(16:0/18:0), in particular, consists of one chain of palmitic acid at the C-1 position and one chain of stearic acid at the C-2 position. The palmitic acid moiety is derived from fish oils, milk fats, vegetable oils and animal fats, while the stearic acid moiety is derived from animal fats, coco butter and sesame oil. The inositol group that is part of every phosphatidylinositol lipid is covalently linked to the phosphate group that acts as a bridge to the lipid tail. In most organisms, the stereochemical form of this inositol is myo-D-inositol (with one axial hydroxyl in position 2 with the remainder equatorial), although other forms can be found in certain plant phosphatidylinositols. Phosphatidylinositol is especially abundant in brain tissue, where it can amount to 10% of the phospholipids, but it is present in all tissues and cell types. There is usually less of it than of phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine. In animal tissues, phosphatidylinositol is the primary source of the arachidonic acid required for biosynthesis of eicosanoids, including prostaglandins, via the action of the enzyme phospholipase A2. Phosphatidylinositol can be phosphorylated by a number of different kinases that place the phosphate moiety on positions 4 and 5 of the inositol ring, although position 3 can also be phosphorylated by a specific kinase. Seven different isomers are known, but the most important in both quantitative and biological terms are phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate. Phosphatidylinositol and the phosphatidylinositol phosphates are the main source of diacylglycerols that serve as signaling molecules, via the action of phospholipase C enzymes.While most phospholipids have a saturated fatty acid on C-1 and an unsaturated fatty acid on C-2 of the glycerol backbone, the fatty acid distribution at the C-1 and C-2 positions of glycerol within phospholipids is continually in flux, owing to phospholipid degradation and the continuous phospholipid remodeling that occurs while these molecules are in membranes. PIs contain almost exclusively stearic acid at carbon 1 and arachidonic acid at carbon 2. PIs composed exclusively of non-phosphorylated inositol exhibit a net charge of -1 at physiological pH. Molecules with phosphorylated inositol (such as PIP, PIP2, PIP3, etc.) are termed polyphosphoinositides. The polyphosphoinositides are important intracellular transducers of signals emanating from the plasma membrane. The synthesis of PI involves CDP-activated 1,2-diacylglycerol condensation with myo-inositol.
Structure
Thumb
Synonyms
ValueSource
1-Hexadecanoyl-2-octadecanoyl-sn-glycero-3-phospho-(1'-myo-inositol)HMDB
1-Palmitoyl-2-stearoyl-sn-glycero-3-phosphoinositolHMDB
Phosphatidylinositol(16:0/18:0)HMDB
Phosphatidylinositol(34:0)HMDB
PI(34:0)HMDB
pino(16:0/18:0)HMDB
pino(34:0)HMDB
1-hexadecanoyl-2-octadecanoyl-sn-glycero-3-phosphoinositol; Phosphatidylinositol(16:0/18:0)Lipid Annotator
PI(16:0/18:0)Lipid Annotator
1-hexadecanoyl-2-octadecanoyl-sn-glycero-3-phosphoinositolLipid Annotator
Chemical FormulaC43H83O13P
Average Molecular Weight839.0851
Monoisotopic Molecular Weight838.557129254
IUPAC Name[(2R)-3-(hexadecanoyloxy)-2-(octadecanoyloxy)propoxy]({[(1s,3R)-2,3,4,5,6-pentahydroxycyclohexyl]oxy})phosphinic acid
Traditional Name(2R)-3-(hexadecanoyloxy)-2-(octadecanoyloxy)propoxy([(1s,3R)-2,3,4,5,6-pentahydroxycyclohexyl]oxy)phosphinic acid
CAS Registry NumberNot Available
SMILES
[H][C@@](COC(=O)CCCCCCCCCCCCCCC)(COP(O)(=O)O[C@H]1C(O)C(O)C(O)[C@@H](O)C1O)OC(=O)CCCCCCCCCCCCCCCCC
InChI Identifier
InChI=1S/C43H83O13P/c1-3-5-7-9-11-13-15-17-18-20-22-24-26-28-30-32-37(45)55-35(34-54-57(51,52)56-43-41(49)39(47)38(46)40(48)42(43)50)33-53-36(44)31-29-27-25-23-21-19-16-14-12-10-8-6-4-2/h35,38-43,46-50H,3-34H2,1-2H3,(H,51,52)/t35-,38?,39-,40?,41?,42?,43-/m1/s1
InChI KeyNEXFZIYXCPIHEF-HGTJTCKHSA-N
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as phosphatidylinositols. These are glycerophosphoinositols where the glycerol is esterified with two fatty acids.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassGlycerophospholipids
Sub ClassGlycerophosphoinositols
Direct ParentPhosphatidylinositols
Alternative Parents
Substituents
  • Diacylglycerophosphoinositol
  • Inositol phosphate
  • Cyclohexanol
  • Dialkyl phosphate
  • Fatty acid ester
  • Cyclitol or derivatives
  • Fatty acyl
  • Alkyl phosphate
  • Dicarboxylic acid or derivatives
  • Phosphoric acid ester
  • Organic phosphoric acid derivative
  • Cyclic alcohol
  • Carboxylic acid ester
  • Secondary alcohol
  • Carboxylic acid derivative
  • Polyol
  • Hydrocarbon derivative
  • Organic oxide
  • Alcohol
  • Carbonyl group
  • Organic oxygen compound
  • Organooxygen compound
  • Aliphatic homomonocyclic compound
Molecular FrameworkAliphatic homomonocyclic compounds
External Descriptors
Ontology
Disposition

Biological location:

  Cell and elements:

  Subcellular:

  Biofluid and excreta:

  Organ and components:

  Tissue and substructures:

Source:

Role

Biological role:

Industrial application:

Process

Naturally occurring process:

  Biological process:

    Cellular process:

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 Solubility0.00076 g/LALOGPS
logP7.22ALOGPS
logP9.88ChemAxon
logS-6ALOGPS
pKa (Strongest Acidic)1.83ChemAxon
pKa (Strongest Basic)-3.6ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count9ChemAxon
Hydrogen Donor Count6ChemAxon
Polar Surface Area209.51 ŲChemAxon
Rotatable Bond Count40ChemAxon
Refractivity219.77 m³·mol⁻¹ChemAxon
Polarizability99.48 ųChemAxon
Number of Rings1ChemAxon
Bioavailability0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-05aj-0071190000-5e8452a81c4119fb54c4View in MoNA
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane
Biofluid Locations
  • Blood
Tissue Location
  • All Tissues
  • Brain
PathwaysNot Available
NameSMPDB/PathwhizKEGG
Normal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
BloodDetected and Quantified0.473 +/- 0.101 uMAdult (>18 years old)BothNormal details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB026971
KNApSAcK IDNot Available
Chemspider ID24767666
KEGG Compound IDC00626
BioCyc IDPhosphatidylinositols
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem CompoundNot Available
PDB IDNot Available
ChEBI IDNot Available
References
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General ReferencesNot Available

Only showing the first 10 proteins. There are 80 proteins in total.

Enzymes

General function:
Involved in calcium ion binding
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes.
Gene Name:
PLCB1
Uniprot ID:
Q9NQ66
Molecular weight:
138565.805
General function:
Involved in calcium ion binding
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes. This form has a role in retina signal transduction.
Gene Name:
PLCB4
Uniprot ID:
Q15147
Molecular weight:
136105.065
General function:
Involved in calcium ion binding
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes.
Gene Name:
PLCB2
Uniprot ID:
Q00722
Molecular weight:
134023.21
General function:
Involved in calcium ion binding
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes.
Gene Name:
PLCB3
Uniprot ID:
Q01970
Molecular weight:
138797.725
General function:
Involved in phosphoinositide phospholipase C activity
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes. It is a crucial enzyme in transmembrane signaling.
Gene Name:
PLCG2
Uniprot ID:
P16885
Molecular weight:
147868.67
General function:
Involved in calcium ion binding
Specific function:
Mediates the production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). Plays an important role in the regulation of intracellular signaling cascades. Becomes activated in response to ligand-mediated activation of receptor-type tyrosine kinases, such as PDGFRA, PDGFRB, FGFR1, FGFR2, FGFR3 and FGFR4. Plays a role in actin reorganization and cell migration.
Gene Name:
PLCG1
Uniprot ID:
P19174
Molecular weight:
148658.92
General function:
Involved in calcium ion binding
Specific function:
The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes. Essential for trophoblast and placental development.
Gene Name:
PLCD1
Uniprot ID:
P51178
Molecular weight:
88134.23
General function:
Involved in N-acetylglucosaminylphosphatidylinositol de
Specific function:
Involved in the second step of GPI biosynthesis. De-N-acetylation of N-acetylglucosaminyl-phosphatidylinositol.
Gene Name:
PIGL
Uniprot ID:
Q9Y2B2
Molecular weight:
28530.965
General function:
Involved in phosphatidylinositol N-acetylglucosaminyltransferase activity
Specific function:
Part of the complex catalyzing the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to phosphatidylinositol, the first step of GPI biosynthesis.
Gene Name:
PIGQ
Uniprot ID:
Q9BRB3
Molecular weight:
65343.25
General function:
Involved in biosynthetic process
Specific function:
Necessary for the synthesis of N-acetylglucosaminyl-phosphatidylinositol, the very early intermediate in GPI-anchor biosynthesis.
Gene Name:
PIGA
Uniprot ID:
P37287
Molecular weight:
54126.065

Only showing the first 10 proteins. There are 80 proteins in total.