Shorthand notation for Glycerophospholipids (GP)
From LipidomicsWiki
Rules for the annotation
- Shorthand notation: Lipid class abbreviation followed by number of C-atoms:number of double bonds.
- Fatty acids linked to the glycerol are known:
- separator _: sn-position of the fatty acids is not known
- separator /: sn-position of fatty acids is proven (order sn-1/sn-2/sn-3 for GL; sn-1/sn-2 or sn-2/sn-3 for GP); no FA linked 0:0
- Other bond types than ester bonds are indicated as follows in front of the sum of C-atoms or fatty acid:
- O = proven O-alkyl-bond (it is important to note that “O” after the number of carbons designates a keto bond)
- P = proven O-alk-1-enyl-bond (acid-sensitive ether bond in “plasmalogens”).
- More than one "non"-ester bond is indicated in front of the bond type as d for di, t for tri.
- Lysophospholipid classes are abbreviated as stated in the LIPID MAPS nomenclature. Where applicable they can be presented formally by their respective phospholipid class indicating the empty sn-position by 0:0.
- Four ether bonds are indicated in front of the bond type as tetra, abbreviated e.
- ForBMP and CL classes the sn-position order will be sn-2/sn-3/sn-2'/sn-3' and sn-1/sn-2/sn-1'/sn-2', respectively.
- Rules for phosphoinositides require additional information if the position of phosphates on the inositol ring are known. The exception is PI3,4,5P3 since the only known tris isomer is 3,4,5. Whilst phosphoinositides are generally presented as PIP2 and PIP3 we have adopted the annotation PIP2 and PIP3 for ease of handling by databases. Should additional species be identified this will require further clarification.
Lipid class abbreviations
- Bismonoacylglycerolphosphate - BMP
- Cardiolipin - CL
- Phosphatidic acid - PA
- Phosphatidylcholine - PC
- Phosphatidylethanolamine - PE
- Phosphatidylgylcerol - PG
- Phosphatidylgylcerolphosphate - PGP
- Phosphatidylinositol - PI
- Phosphatidylinositol-monophosphate - PIP
- Phosphatidylinositol-3-phosphate - PIP[3’]
- Phosphatidylinositol-4-phosphate - PIP[4’]
- Phosphatidylinositol-5-phosphate - PIP[5’]
- Phosphatidylinositol-bisphosphate - PIP2
- Phosphatidylinositol-3,4-bisphosphate - PIP2[3’,4’]
- Phosphatidylinositol-3,5-bisphosphate - PIP2[3’,5’]
- Phosphatidylinositol-4,5-bisphosphate - PIP2[4’,5’]
- Phosphatidylinositol-trisphosphate – PIP3
- Phosphatidylserine – PS
- Lysophospholipids - Prefix L
Examples
| Bond type | Lipid class level mass$ | Lipid species level§ | Bond type level | Fatty acyl/alkyl level | Fatty acyl/alkyl position level | LIPID MAPS Fatty acyl/alkyl structure level |
|---|---|---|---|---|---|---|
| Diacyl | BMP (690) | BMP 34:2 | BMP 34:2 | BMP 16:0_18:2 | BMP 16:0/0:0/18:2/0:0 sn-2/sn-3/sn-2'/sn-3' | BMP 16:0/0:0/18:2(9Z,12Z)/0:0 sn-2/sn-3/sn-2'/sn-3' |
| Tetraacyl | CL (1450) | CL 72:7 | CL 72:7 | CL 18:1_18:2_18:2_18:2 CL 36:3_36:4 (known DG fragments) | CL 18:1/18:2/18:2/18:2 sn-1/sn-2/sn-1'/sn-2' | CL 18:1(9Z)/18:2(9Z,12Z)/ 18:2(9Z,12Z)/18:2(9Z,12Z) sn-1/sn-2/sn-1'/sn-2' |
| Tetraalkyl | CL (1521) | CL 76:0 | CL eO-80:0 | CL O-20:0/O-20:0/O‑20:0 /O-20:0 | CL O-20:0/O-20:0/O-20:0/ O‑20:0 | CL O‑16:0(3Me,7Me,11Me,15Me)/ O‑16:0(3Me,7Me,11Me,15Me)/ O‑16:0(3Me,7Me,11Me,15Me)/ O‑16:0(3Me,7Me,11Me,15Me) |
| Diacyl | PC (759) | PC 34:1 | PC 34:1 | PC 16:0_18:1 | PC 16:0/18:1 | PC 16:0/18:1(9Z) |
| Alkyl-acyl | PC (745) | PC O-34:1 | PC O-34:1 | PC O-16:0_18:1 | PC O-16:0/18:1 | PC O-16:0/18:1(9Z) |
| Dialkyl | PC (731) | PC 32:1 | PC dO-34:1 | PC O-16:0_O-18:1 | PC O-16:0/O-18:1 | PC O-16:0/O-18:1 |
| Diacyl | PE (717) | PE 34:1 | PE 34:1 | PE 16:0_18:1 | PE 16:0/18:1 | PE 16:0/18:1(9Z) |
| Plasmalogen | PE (701) | PE O-34:2 | PE O-34:2 | PE P-16:0_18:1 §§ | PE P-16:0/18:1 §§ | PE P-16:0/18:1(9Z) |
| Triacyl | LCL (1188) | LCL 54:5 | LCL 54:5 | LCL 18:1_18:2_18:2 | LCL 18:1/18:2/18:2/0:0 | LCL 18:1(9Z)/18:2(9Z,12Z)/18:2(9Z,12Z)/0:0 |
| Acyl | LPC (495) | LPC 16:0 | LPC 16:0 | LPC 16:0 or PC 16:0_0:0 | LPC 16:0/0:0 or PC 16:0/0:0 | LPC 16:0/0:0 or PC 16:0/0:0 |
| Alkyl | LPC (481) | LPC O-16:0 | LPC O-16:0 | LPC O-16:0 | LPC O-16:0/0:0 | LPC O-16:0/0:0 |
| Alkyl/Alk-1-enyl | LPC (479) | LPC O-16:1 | LPC O-16:1 | LPC O-16:1 | LPC O-16:1/0:0 | LPC O-16:1(9Z)/0:0 |
$ m is the uncharged molecular mass
§ Annotation based on the assumption of even numbered carbon chains only
§§ Identification of plasmalogens (alk-1-enyl bond) require specific MS analysis
| Bond type | Lipid class level mass$ | Lipid species level§ | Bond type level | Phosphate position | Fatty acyl/alkyl level | Fatty acyl/alkyl position level | LIPID MAPS Fatty acyl/alkyl structure level |
|---|---|---|---|---|---|---|---|
| Diacyl | PIP (966) | PIP 38:4 | PIP 38:4 | PIP[3’] 38:4 | PIP[3’] 18:0_20:4 | PIP[3’] 18:0/20:4 | PIP[3’] 18:0/20:4(4Z,8Z,11Z, 4Z) |
| Diacyl | PIP2 (1046) | PIP2 38:4 | PIP2 38:4 | PIP2[4’,5’] 38:4 | PIP2[4’,5’] 18:0_20:4 | PIP2[4’,5’] 18:0/20:4 | PIP2[4’,5’] 18:0/20:4(4Z,8Z,11Z, 4Z) |
