Monosaccharide residues are named and abbreviated (Table 1) according to the proposed rules of nomenclature recommendations for carbohydrates [4] (see also the nomenclature of glycoproteins [2]). The D and L configurational symbols are generally omitted; all monosaccharides are D with the exception of fucose and rhamnose which are L unless otherwise specified.
TABLE 1.
Recommended abbreviations for some monosaccharides, derivatives and related compounds
| Name | Symbol | ||
|---|---|---|---|
| N-acetylgalactosamine | GalNAc | ||
| N-acetylglucosamine | GlcNAc | ||
| N-acetylneuraminic acid1 | Neu5Ac or NeuAc | ||
| 5,9-N,O-diacetylneuraminic acid1 | Neu5,9Ac2 | ||
| fucose (6-deoxygalactose) | Fuc | ||
| galactitol | Gal-ol | ||
| galactosamine | GalN | ||
| galactopyranose 3-sulfate | Galp3S | ||
| galactose | Gal | ||
| galacturonic acid | GalA | ||
| glucitol | Glc-ol | ||
| glucosamine | GlcN | ||
| glucose | Glc | ||
| glucose 6-phosphate | Glcp6P | ||
| glucuronic acid | GlcA | ||
| N-glycoloylneuraminic acid1 | Neu5Gc or NeuGc | ||
| myo-inositol2 | Ins | ||
| mannose | Man | ||
| 4-O-methylgalactose | Gal4Me | ||
| rhamnose | Rha | ||
| xylose | Xyl |
Neutral glycosphingolipids with oligosaccharide chains
5.3.1. Systematic names for glycosphingolipids with larger oligosaccharide chains become rather cumbersome. It is therefore recommended to use semi-systematic names in which trivial names for "root" structures are used as a prefix. The recommended root names and structures are given in Table 2.
The name of a given glycosphingolipid is then composed of (root name)(root size)osylceramide. Thus, lactotetraosylceramide designates the second structure listed in Table 2 linked to a ceramide. When referring to particular glycose residues Roman numerals are used (Lip-3.9 in [1]), counting from the ceramide (see Table 2).
TABLE 2. Root names and structures
| Root | Symbol | Root structure |
|---|---|---|
IV III II I | ||
| ganglio | Gg | Galb3GalNAcb4Galb4Glc- |
| lacto1 | Lc | Galb3GlcNAcb3Galb4Glc- |
| neolacto2 | nLc | Galb4GlcNAcb3Galb4Glc- |
| globo | Gb | GalNAcb3Gala4Galb4Glc- |
| isoglobo2 | iGb | GalNAcb3Gala3Galb4Glc- |
| mollu | Mu | GlcNAcb2Mana3Manb4Glc- |
| arthro | At | GalNAcb4GlcNAcb3Manb4Glc- |
The Svennerholm abbreviations for brain gangliosides
In this system, the fact that we are dealing with gangliosides is indicated by the letter G, the number of sialic acid residues is stated by M for mono-, D for di-, T for tri- and Q for tetrasialoglycosphingolipids. A number is then assigned to the individual compound which referred initially to its migration order in a certain chromatographic system [13].
Though these designations are far from being systematic, and it is impossible to derive the structure from them, they have the advantage of being short and well understood since they have been in use for a long time. A list of these abbreviations is given in Table 3.
Since there is no clear-cut system in these abbreviations, it is not recommended to extend the list by coining new symbols of this kind. As a result, the following two cases are examples of abbreviations that should not be used.
1) A disialoganglioside, Neu5Aca3Galb3(Neu5Aca6)GalNAcb4Galb4GlcCer has been abbreviated GD1a. This practice should be discontinued. The recommended abbreviation for this compound is IV3-a-Neu5Ac,III6-a-Neu5Ac-Gg4Cer.
2) The system has been extended to gangliosides of other "root" types, such as those derived from lactotetraosylceramide. An example of this kind is the widely distributed ganglioside called sialoparagloboside, Neu5Aca3Galb4GlcNAcb3Galb4GlcCer, which has at times been abbreviated LM1, but should be referred to as IV3-a-Neu5Ac-nLc4Cer.
TABLE 3. Some abbreviations using the Svennerholm system
| Structure | Abbreviation* |
|---|---|
| Neu5Aca3Galb4GlcCer | GM3 |
| GalNAcb4(Neu5Aca3)Galb4GlcCer | GM2 |
| Galb3GalNAcb4(Neu5Aca3)Galb4GlcCer | GM1a |
| Neu5Aca3Galb3GalNAcb4Galb4GlcCer | GM1b |
| Neu5Aca8Neu5Aca3Galb4GlcCer | GD3 |
| GalNAcb4(Neu5Aca8Neu5Aca3)Galb4GlcCer | GD2 |
| Neu5Aca3Galb3GalNAcb4(Neu5Aca3)Galb4GlcCer | GD1a |
| Galb3GalNAcb4(Neu5Aca8Neu5Aca3)Galb4GlcCer | GD1b |
| Neu5Aca8Neu5Aca3Galb3GalNAcb4(Neu5Aca3)Galb4GlcCer | GT1a |
| Neu5Aca3Galb3GalNAcb4(Neu5Aca8Neu5Aca3)Galb4GlcCer | GT1b |
| Galb3GalNAcb4(Neu5Aca8Neu5Aca8Neu5Aca3)Galb4GlcCer | GT1c |
| Neu5Aca8Neu5Aca3Galb3GalNAcb4(Neu5Aca8Neu5ca3)Galb4GlcCer | GQ1b |
Source: http://www.chem.qmul.ac.uk/iupac/misc/glylp.html
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