Research 312 (1998) 167±175

Nomenclature of

These are recommendations of the IUPAC-IUBMB Joint Commission on Biochemical Nomenclature (JCBN), whose members are A. Cornish-Bowden (Chairman, France), A. J. Barrett (UK), R. Cammack (UK), M. A. Chester (Sweden), D. Horton (USA), C. Lie becq (Belgium), K. F. Tipton (Ireland), B. J. Whyte (Secretary, Switzerland).

JCBN thanks a panel convened by C. C. Sweeley (USA), whose members were S. Basu (USA), H. Egge (Germany), G. W. Hart (USA, co-opted), S. Hakomori (USA), T. Hori (Japan: deceased 1994), P. Karlson (Germany), R. Laine (USA), R. Ledeen (USA), B. Macher (USA), L. Svennerholm (Sweden), G. Tetta- manti (Italy) and H. Wiegandt (Germany), for drafting the recommendations; and other present or former members of the Nomenclature Committee of IUBMB (NC-IUBMB), former members of JCBN, and invi- ted observers, namely A. Bairoch (Switzerland), H. Berman (USA), C. R. Cantor (USA), H. B. F. Dixon (UK), M. A. C. Kaplan (Brazil), K. L. Loening (USA), A. McNaught (UK), G. P. Moss (UK), J. C. Rigg (The Netherlands), W. Saenger (Germany), N. Sharon (Israel), P. Venetianer (Hungary), J. F. G. Vlie- genthart (The Netherlands).

Acknowledgement. This document was ®rst published in Pure Appl. Chem. 69, 2475-2487 (1997): # 1997 IUPAC.

A World Wide Web version, prepared by G. P. Moss, is available at http://www.chem.qmw.ac.uk/iupac/ misc/glylp.html

Contents GL-4. Classi®cation of glycolipids based on their moieties GL-1. General considerations 4.1. Glycoglycerolipids GL-2. Generic terms 4.2. Glycophosphatidylinositols 2.1. 4.3. 2.2. Glycoglycerolipid GL-5. Neutral glycosphingolipids 2.3. 5.1. Monoglycosylceramides 2.4. Glycophosphatidylinositol 5.2. Diosylceramides 2.5. Psychosine 5.3. Neutral glycosphingolipids with 2.6. Other names oligosaccharide chains GL-3. Principles of nomenclature GL-6. Acidic glycosphingolipids 3.1. Number of monosaccharide residues 6.1. 3.2. Naming of monosaccharide residues 6.2. Glycuronoglycosphingolipids 3.3. Use of symbols for de®ning 6.3. Sulfatoglycosphingolipids oligosaccharide structures 6.4. Phosphoglycosphingolipids 3.4. Ring size and conformation 6.5. Phosphonoglycosphingolipids

0008-6215/98/$Ðsee front matter # 1998 Published by Elsevier Science Ltd. All rights reserved PII S0008-6215(98)00231-6 168 Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175

GL-7. Short abbreviations GL-2.3. Glycosphingolipid.ÐThe term glyco- 7.1. Recommended abbreviations designates containing at least 7.2. The Svennerholm abbreviations for one monosaccharide residue and either a sphingoid brain gangliosides or a . The glycosphingolipids can be sub- divided as follows: GL-8. References (A) Neutral glycosphingolipids: 1. mono-, oligo-, and polyglycosylsphingoids GL-1. General considerations 2. mono-, oligo-, and polyglycosylceramides. (B) Acidic glycosphingolipids: Glycolipids are glycosyl derivatives of lipids such 1. sialoglycosphingolipids (gangliosides, con- as acylglycerols, and prenols. They are taining one or more sialic acid residues) collectively part of a larger family of substances 2. uronoglycosphingolipids (containing one or known as . The major types of more uronic acid residues) glycoconjugates are glycoproteins, glycopeptides, 3. sulfoglycosphingolipids (containing one or peptidoglycans, proteoglycans, glycolipids and more carbohydrate-sulfate ester groups) lipopolysaccharides. The structures of glycolipids 4. phosphoglycosphingolipids (containing one or are often complex and dicult to reproduce in the more phosphate mono- or diester groups) text of articles and certainly cannot be referred to 5. phosphonoglycosphingolipids [containing one or in oral discussions without a nomenclature that more (2-aminoethyl)hydroxyphosphoryl groups]. implies speci®c chemical structural features. The 1976 recommendations [1] on lipid nomen- clature contained a section (Lip-3) on glycolipids, GL-2.4. Glycophosphatidylinositol.ÐThe term with symbols and abbreviations as well as trivial glycophosphatidylinositol is used to designate gly- names for some of the most commonly occurring colipids which contain saccharides glycosidically glycolipids. Since then, more than 300 new glycoli- linked to the inositol moiety of phosphatidylinositols pids have been isolated and characterized, some (e.g. diacyl-sn-glycero-3-phosphoinositol), inclusive having carbohydrate chains with more than 20 of lyso- (Lip-2.6 in [1]) species and those with various monosaccharide residues and others with struc- O-acyl-, O-alkyl-, O-alk-1-en-1-yl- (e.g. plasmanyli- tural features such as inositol phosphate. The nositols; [5]) or other substitutions on their glycerol nomenclature needs to be convenient and practical, or inositol residues. as well as extensible, to accommodate newly dis- GL-2.5. Psychosine.ÐPsychosine was coined covered structures. It should also be consistent with historically to designate a monoglycosylsphingoid the nomenclature of glycoproteins, glycopeptides (i.e. not acylated). The use of this term is not and peptidoglycans [2], oligosaccharides [3], and encouraged (Lip-3.4 in [1]). in general [4]. GL-2.6. Other names.ÐOther terms such as This document supersedes the glycolipid sec- fucoglycosphingolipid, mannoglycosphingolipid, tion in the 1976 Recommendations on lipid xyloglycosphingolipid, etc., may be used when it is nomenclature [1]. important to highlight a certain structural feature of the glycolipid.

GL-2. Generic terms GL-3. Principles of nomenclature GL-2.1. Glycolipid.ÐThe term glycolipid desig- nates any compound containing one or more GL-3.1. Number of monosaccharide residues.Ð monosaccharide residues bound by a glycosidic The number of monosaccharide residues in an oli- linkage to a hydrophobic moiety such as an acyl- gosaccharide is indicated by suxes such as ``diosyl'', glycerol, a sphingoid, a ceramide (N-acylsphingoid) ``triaosyl'', ``tetraosyl'' etc. [1,6]. Thus, the general or a prenyl phosphate. name for the oligosaccharide residue of all glyco- GL-2.2. Glycoglycerolipid.ÐThe term glycogly- containing 10 monosaccharide resi- cerolipid is used to designate glycolipids containing dues is ``glycodecaosyl''; it might be a glycodecaosyl- one or more glycerol residues. ceramide or a 3-glycodecaosyl-1,2-diacyl-sn-glycerol. Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175 169

Table 1 structures. A ``short form'' for representing Recommended abbreviations for some monosaccharides, sequences more brie¯y can be used for specifying derivatives and related compounds large structures. Positions of glycosidic linkages are Name Symbol still given, but the number of the anomeric carbon is N-acetylgalactosamine GalNAc omitted, since this is invariable for each mono- N-acetylglucosamine GlcNAc saccharide, i.e. C-1 for Glc, etc; C-2 for Neu5Ac, etc. N-acetylneuraminic acida Neu5Ac or NeuAc Example: a 5,9-N,O-diacetylneuraminic acid Neu5,9Ac2 fucose (6-deoxygalactose) Fuc -d-Galp- 1!3†- -d-Galp- extended form† galactitol Gal-ol galactosamine GalN or Gal 13† Gal - condensed form† galactopyranose 3-sulfate Galp3S or Gal 3Gal - or Gal -3Gal - short form†: galactose Gal galacturonic acid GalA glucitol Glc-ol GL-3.4. Ring size and conformation.ÐRing size glucosamine GlcN and conformation should be designated only when glucose Glc glucose 6-phosphate Glc6P ®rmly established from NMR or other experimental glucuronic acid GlcA data. Previously published recommendations on N-glycoloylneuraminic acida Neu5Gc or NeuGc the speci®cation of conformation should be con- myo-inositolb Ins mannose Man sulted [9,10]. 4-O-methylgalactose Gal4Me Example: rhamnose Rha xylose Xyl 4 -d-galactopyranosyl- C1- 1!3†- -d- 4 aAcylated neuraminic acids and other derivatives of neur- galactopyranosyl- C1- 4 4 aminic acid may also be called sialic acids (abbreviated Sia) or Galp C1 3Galp C1 -: when the nature of the N-acyl substituent(s) is not relevant, or is unknown [7]. bmyo-Inositol with the numbering of the 1D con®guration [8]. Subsequently, examples will usually be in the more traditional form with parentheses and both anomeric locants, as for example Gal( 1-4)Glc-, but it is understood that the short form (i.e. Note 1: ``diosyl'' not ``biosyl'' is the correct sux. Gal 4Glc-) is also acceptable. Note 2: The ``a'' in ``tetraosyl'', etc., is not elided in order to di€erentiate a tetrasaccharide residue (tetraosyl) from a four carbon sugar (tetrose), etc. GL-4. Classi®cation of glycolipids based on their The ``a'' in ``triaosyl'' is added for a similar reason. lipid moieties Recommendations have been made for the nomenclature of oligosaccharides [3,4]. GL-4.1. Glycoglycerolipids.ÐEsters, ethers and GL-3.2. Naming of monosaccharide residues.Ð glucose derivatives of glycerol are designated by a Monosaccharide residues are named and abbre- pre®x, denoting the substituent, preceded by a viated (Table 1) according to the proposed locant. As previously discussed in detail [1], the nomenclature recommendations for carbohydrates carbon atoms of glycerol are numbered stereo- [4] (see also the nomenclature of glycoproteins [2]). speci®cally, with carbon atom 1 at the top of the The d and l con®gurational symbols are generally formula shown below. To di€erentiate this num- omitted; all monosaccharides are d with the bering system from others that have been used, the exception of fucose and rhamnose which are l glycerol is always accompanied by the pre®x sn (for unless otherwise speci®ed. stereospeci®cally numbered, Lip-1.13 in [1]) in sys- GL-3.3. Use of symbols for de®ning oligosacch- tematic and abbreviated names. aride structures.ÐUsing the condensed system of carbohydrate nomenclature [Ref. 2, section 3.7: Ref. 4, 2-Carb-38.5], positions of glycosidic lin- kages and anomeric con®gurations are expressed in parentheses between the monosaccharide residues that are thus linked. This principle should be adhered to in full names as well as the abbreviated 170 Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175

Example: generically been termed ``glycoinositolpho- spholipids'' to distinguish them from those cova- lently attached to proteins or larger structures. GL-4.3. Glycosphingolipids.Ð4.3.1. A glyco- sphingolipid is a carbohydrate-containing deriva- tive of a sphingoid or ceramide. It is understood that the carbohydrate residue is attached by a gly- cosidic linkage to O-1 of the sphingoid. 4.3.2. Sphingoids are long-chain aliphatic amino alcohols. The basic chemical structure is repre- sented by the compound originally called ``dihy- GL-4.2. Glycophosphatidylinositols.Ð4.2.1. Gly- drosphingosine'' [(2S,3R)-2-aminooctadecane-1,3- cophosphatidylinositol (GPI) nomenclature should diol]. This sphingoid should now be referred to [1] incorporate the accepted IUB-IUPAC recommen- as sphinganine (I). dations [1,2] for the naming of phospholipids and The terms sphinganine, sphing-4-enine etc. imply the glycan portions of glycolipids or glycoproteins. a chain length of 18 carbon atoms. Chain-length While the diversity of glycophosphatidylinositol homologs are named by the root chemical name of structures is only beginning to be realized (for the parent hydrocarbon. For example, the sphin- reviews see [11,12]), many appear to have a com- goid with 20 carbon atoms is icosasphinganine and mon ``core''. the sphingoid with 14 carbon atoms is tetra- decasphinganine. Unsaturated derivatives of sphinganine and other sphingoids should be de®ned in terms of the location and con®guration of each ole®nic center. The most commonly occurring unsaturated sphin- goid was originally called ``'' [(2S, 3R,4E)-2-aminooctadec-4-ene-1,3-diol]. It should now be referred to as (E)-sphing-4-enine (II). The trivial name ``sphingosine'' can be retained. As a

second example, a C18 sphingoid with two trans double bonds at 4,14 should be called (4E,14E)- sphinga-4,14-dienine. Substituents such as hydroxy, oxo, methyl, etc. are referred to by appropriate suxes that denote the position of each substituent. The sphingoid containing a hydroxyl group at C-4 of sphinganine 4.2.2. Glycophosphatidylinositols covalently was originally called phytosphingosine. According attached to polypeptides are termed ``GPI- to the nomenclature adopted in 1976 [1], it should anchors''. Generally, such anchors are covalently be called (2S,3S,4R)-2-aminooctadecane-1,3,4- attached to the C- terminus of a polypeptide via an triol. A trivial (but incorrect) name is (R)-4-hydro- amide linkage to 2-aminoethanol, which is linked xysphinganine (III). to the terminal core mannose residue via a phos- 4.3.3. Ceramides are N-acylated sphingoids. The phodiester bond on O-6 of the mannose. A core fatty acids of naturally occurring ceramides range in

Man 2Man 6Man 4GlcN 6 glycan structure is chain length from about C16 to about C26 and may attached to the inositol (generally d-myo-inositol) contain one or more double bonds and/or hydroxyl of phosphatidylinositol. The non-acetylated GlcN is substituents at C-2. The complete chemical name a characteristic feature of glycophosphatidyl-inosi- for a speci®c ceramide includes the sphingoid and tols. Anchor structures appear to vary considerably fatty acyl substituents. For example, a ceramide both in terms of modi®cations on the core glycan and containing 2-hydroxyoctadecanoic acid and with respect to additional modi®cations of the inosi- sphing-4-enine should be called (E)-N-(2-hydro- tol residue. Free glycophosphatidylinositols have xyoctadecanoyl)]sphing-4-enine. Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175 171

GL-5. Neutral glycosphingolipids Roman numerals are used (Lip-3.9 in [1]), counting from the ceramide (see Table 2). GL-5.1. Monoglycosylceramides.ÐThe trivial The use of the pre®x ``nor'' for unbranched oli- name ``'' was historically used for the gosaccharide chains should be abandoned since substance from brain, -galactosyl(1$1)ceramide, this pre®x has a well-de®ned meaning (``one carbon and was later modi®ed to include -gluco- atom less'') in organic chemistry nomenclature. syl(1$1)ceramide from the spleen of a patient with 5.3.2. The root name applies also to structures Gaucher's disease. It has become a general term for that are shorter than the root given in Table 2. these two kinds of monoglycosylceramides. How- Thus, gangliotriaosylceramide is the name for the ever, since other monosaccharides are found in this structure GalNAc 4Gal 4GlcCer, where the class, the more structurally explicit terms such as fourth, terminal residue is missing. The trisacchar- glucosylceramide (GlcCer or better, Glc 1Cer), ides obtained from the lacto and neolacto series are (GalCer), xylosylceramide identical and in this case the former (shorter) name (XylCer), etc. should be used. should be used. GL-5.2. Diosylceramides.ÐDiosylceramides may 5.3.3. In the lacto series, the residues III and be named systematically, e.g. -d-galactosyl-(1!4) IV can form a repeating unit. Thus, names like - -d-glucosyl-(1$1)-ceramide. However, it is often more convenient to use the trivial name of the dis- Table 2 accharide and call the structure given above lacto- Root names and structures sylceramide (LacCer). Root Symbol Root structure GL-5.3. Neutral glycosphingolipids with oligo- saccharide chains.Ð5.3.1. Systematic names for IV III II I ganglio Gg Gal 3GalNAc 4Gal 4Glc- glycosphingolipids with larger oligosaccharide lactoa Lc Gal 3GlcNAc 3Gal 4Glc- chains become rather cumbersome. It is therefore neolactob nLc Gal 4GlcNAc 3Gal 4Glc- recommended to use semi-systematic names in globo Gb GalNAc 3Gal 4Gal 4Glc- isoglobob iGb GalNAc 3Gal 3Gal 4Glc- which trivial names for ``root'' structures are used mollu Mu GlcNAc 2Man 3Man 4Glc- as a pre®x. The recommended root names and arthro At GalNAc 4GlcNAc 3Man 4Glc- structures are given in Table 2. aLacto as used here should not be confused with lactose. The name of a given glycosphingolipid is then bNote: The pre®x ``iso'' is used here to denote a (1!3) versus. composed of (root name)(root size)osylceramide. (1!4) di€erence in the linkage position between the mono- Thus, lactotetraosylceramide designates the second saccharide residues III and II, while the term ``neo'' denotes such a di€erence [(1!4) versus. (1!3)] between residues IV structure listed in Table 2 linked to a ceramide. and III. This scheme should be used also in other cases where When referring to particular glycose residues such positional isomers occur, and only in such cases. 172 Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175 neolactohexaosylceramide (not recommended) named accordingly even when linked to a carbon have been used, even though the chemical nature of atom with a higher number than the member of the the two glycose residues at the non-reducing end root oligosaccharide. In oligosaccharide nomen- are not explicit in the name. clature [4] the longest chain is the parent structure. If two chains are of equal length the one with lower -d-Galp- 1!4†- -GlcpNAc- 1!3†- -d-Galp- locants at the branch points is preferred, although 1!4†- -GlcpNAc- 1!3†- -d-Galp- 1!4† some oligosaccharides are traditionally depicted - -d-Glcp- 1$1†Cer otherwiseÐfrequently NeuAc and Fuc derivatives. or Gal 4GlcNAc 3Gal 4GlcNAc 3Gal 4GlcCer Example: or Gal -4GlcNAc -3Gal -4GlcNAc -3Gal - 4GlcCer: GalNAc 4Gal 4Glc- The correct name is -(N-acetyllactosaminyl)- j (1!3)-neolactotetraosylceramide, where N-acet- Neu5Ac 3 yllactosaminyl is -d-Galp-(1!4)-d-GlcNAc-. or GalNAc 4 Neu5Ac 3†Gal 4Glc-:Otherwise in ‰4Š : Neu5Ac 3 GalNAc 4†Gal 4Glc- 5.3.4. Substances containing glycose residues or II3- -Neu5Ac-Gg -: that are not part of a root structure should be 3 named by referral to the root oligosaccharide and locating the additional substituents by a Roman numeral designating the position of the substituent GL-6. Acidic glycosphingolipids in the root oligosaccharide (counting from the cer- amide end) to which the substituent is attached, GL-6.1. Gangliosides.ÐGangliosides are sia- with an arabic numeral superscript indicating loglycosphingolipids. They are named as N-acetyl- the position on that residue which is sub- or N-glycoloyl-neuraminosyl derivatives of the stituted. The anomeric con®guration should also corresponding neutral glycosphingolipid, using the be speci®ed. nomenclature given in GL-5.3. The position of the Examples: sialic acid residue(s) is indicated in the same way as is the case of a branched structure. i† III 2- -fucosylglobotriaosylceramide Example: or Fuc 2Gal 4Gal 4GlcCer or III 2- -Fuc-Gb Cer 3 IV3- -N-glycoloylneuraminosyl-II3- -N- ii† II 2- -xylosylmollutetraosylceramide acetylneuraminosylgangliotetraosylceramide or GlcNAc 2Man 3 Xyl 2†Man 4GlcCer or Neu5Gc 3Gal 3GalNAc 4Gal 4GlcCer or II 2- -Xyl-Mu Cer: 4 j Neu5Ac 3 3 3 5.3.5. Branched structures should be designated or IV - -Neu5Gc; II - -Neu5Ac-Gg4Cer: in a systematic manner, locating substituents in or Neu5; 9Ac2 3Gal 3GalNAc 4Gal 4GlcCer correlation with the Haworth structure of the mul- j tiply substituted monosaccharide. This principle Neu5Ac 3 3 3 should be applied in full structures as well as linear or IV - -Neu5; 9Ac2; II - -Neu5Ac-Gg4Cer: formulations, wherein substituents are in one or more sets of square brackets. Such names and GL-6.2. Glycuronoglycosphingolipids.ÐThese are abbreviations should refer to the substituent on the best named according to the guidelines of GL-5.2 highest carbon number of the branched mono- and GL-5.3. Special root names have not yet been saccharide ®rst, and proceed toward the sub- assigned. stituent on the lowest carbon number. This GL-6.3. Sulfoglycosphingolipids.ÐThese are gly- recommendation is consistent with the nomen- cosphingolipids carrying a sulfate ester group, for- clature of glycoproteins, glycopeptides and pepti- merly called ``''. They are sometimes doglycans [2] although not explicitly stated termed sulfatoglycosphingolipids. therein. Sulfoglycosphingolipids may also be named as Note: When root names (see GL-5.3.1.) are used, sulfate esters (sulfates) of the neutral glyco- the branches should be treated as side chains and sphingolipids (see GL-5). Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175 173

Example: or Gal4Me 3GalNAc 3 Fuc 4†GlcNAc 2Man 3 Xyl 2† -6- NH2 CH2CH2 P OH†ˆO†Man 4 II3-sulfo-LacCer GlcCer or II3-sulfate: or OH j GL-6.4. Phosphoglycosphingolipids.ÐTwo types NH2CH2CH2 P ˆ O of glycosphingolipids containing phosphodiester j bonds are known: (i) those containing a 2-ami- 6 noethyl phosphate residue esteri®ed to a mono- Gal4Me 3GalNAc 3GlcNAc 2Man 3Man 4GlcCer saccharide residue, and (ii) those with a jj phosphodiester bridge between an inositol residue Fuc 4 Xyl 2 and the ceramide moiety. Those of the ®rst type can be easily named by analogy to the sulfoglycosphingolipids. GL-7. Short abbreviations Example: There are no easy solutions to the dilemma that III6- 2-aminoethanolphospho† has arisen from the discovery of so many (nearly arthrotriaosylceramide 300) glycosphingolipids of diverse structures. Short or 6 EtnP†-GlcNAc 3Man 4GlcCer abbreviations are so attractive that a logical sys- 6 or III -Etn-P-At3Cer: tem, with broad application to more complex compounds, is desirable. The second type can be named as inositolpho- GL-7.1. Recommended abbreviations.ÐA system sphoceramide derivatives. already used (GL-5.3) is based on the abbreviated Example: root names of the oligosaccharide structures. The - N-acetyllactosaminyl†- 1!4†- - full root structures are tetrasaccharides, and glucuronosyl- 1!2†-inositolphosphoceramide sequential removal of terminal monosaccharide or Gal 4GlcNAc 4GlcA 2Ins-1-P-Cer: residues gives smaller, precisely de®ned structures. Elongation of root tetrasaccharides is on the other GL-6.5. Phosphonoglycosphingolipids.ÐThese hand unde®ned and hence ambiguous. The root are glycolipids esteri®ed with an alkylphosphono name may be used, followed by an arabic number acid, i.e. a compound containing a C-P bond. Their indicating the total number of monosaccharide nomenclature is best derived using the pre®x phos- residues. A lower case letter can be added to dif- phoryl that denotes the trivalent radical O ˆ P . ferentiate between particular compounds. The residue Example:

i† Gal 3GalNAc 3Gal 4Gal 4GlcCer 3 or IV - -Gal-Gb4Cer ii† GalNAc 3GalNAc 3Gal 4Gal 4GlcCer 3 or IV - -GalNAc-Gb4Cer: may be termed (2-aminoethyl)hydroxyphosphoryl. The location of this group is given in the same way Either of these compounds could, after de®nition, as other ester groups. be referred to as Gb5Cer. In the presence of both Example: structures the abbreviations Gb5a and Gb5b may be de®ned and used. It is recommended that the use of 4-O-methyl- -d-galactopyranosyl†- 1!3†- 2-acet- ``Ose'', as in GbOse4Cer, be discontinued. amido-2- deoxy- -d-galactopyranosyl† - 1!3†- Since this short form sometimes leads to ambi- ‰ -l-fucopyranosyl- 1!4†Š- 2-acetamido-2-de- guities, the full structure should be given once in a oxy- -d-glucopyranosyl†- 1!2†- -d-mannopy- paper or in a footnote, using the abbreviated form ranosyl - 1!3†-‰ -d-xylopyranosyl- 1!2†Š-6- according to GL-5.3. ‰ 2-aminoethyl†hydroxyphosphorylŠ- -d-manno GL-7.2. The Svennerholm abbreviations for brain pyranosyl- 1!4†- -d -glucopyranosyl- 1$1†- gangliosides.ÐIn this system, the fact that we are ceramide dealing with gangliosides is indicated by the letter 174 Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175

Table 3 been abbreviated LM1, but should be referred Some abbreviations using the Svennerholm system 3 to as IV - -Neu5Ac-nLc4Cer. Structure Abbreviationa Attempts to abbreviate more complex glycos- Neu5Ac 3Gal 4GlcCer GM3 GalNAc 4(Neu5Ac 3)Gal 4GlcCer GM2 phingolipids derived from these examples have Gal 3GalNAc 4(Neu5Ac 3)Gal 4GlcCer GM1a resulted in other illogical abbreviations, such as Fuc- Neu5Ac 3Gal 3GalNAc 4Gal 4GlcCer GM1b 30-LM1 for Neu5Ac 3Gal 4(Fuc 3)GlcNAc 3 Neu5Ac 8Neu5Ac 3Gal 4GlcCer GD3 3 3 GalNAc 4(Neu5Ac 8Neu5Ac 3)Gal 4 GD2 Gal 4GlcCer (IV - -Neu5Ac,III - -Fuc-nLc4Cer). GlcCer More information on the structures of various Neu5Ac 3Gal 3GalNAc 4(Neu5Ac 3) GD1a glycolipids and the biological material from which Gal 4GlcCer Gal 3GalNAc 4(Neu5Ac 8Neu5Ac 3) GD1b they were obtained may be found in several reviews Gal 4GlcCer [14±16]. Neu5Ac 8Neu5Ac 3Gal 3GalNAc 4 GT1a (Neu5Ac 3)Gal 4GlcCer Neu5Ac 3Gal 3GalNAc 4(Neu5Ac 8 GT1b GL-8. References Neu5Ac 3)Gal 4GlcCer Gal 3GalNAc 4(Neu5Ac 8Neu5Ac 8 GT1c [1] IUPAC-IUB Commission on Biochemical Neu5Ac 3)Gal 4GlcCer Nomenclature (CBN). The nomenclature of lipids Neu5Ac 8Neu5Ac 3Gal 3GalNAc 4 GQ1b (Recommendations 1976). Eur. J. Biochem.,79 (Neu5Ac 8Neu5Ac 3)Gal 4GlcCer (1977) 11±21; Hoppe-Seylers Z. Physiol. Chem., a Previously written using subscripts, e.g. GM3, etc. 358 (1977) 617±631; Lipids, 12 (1977)455±468; Mol. Cell. Biochem., 17 (1977) 157±171; Chem. Phys. Lipids, 21 (1978) 159±173; J. Lipid Res., 19 (1978) 114±128; Biochem. J., 171 (1978) 21±35. G, the number of sialic acid residues is stated by M [2] IUPAC-IUB Joint Commission on Biochemical for mono-, D for di-, T for tri- and Q for tetra- Nomenclature (JCBN). Nomenclature of glyco- sialoglycosphingolipids. A number is then assigned proteins, glycopeptides and peptidoglycans to the individual compound which referred initially (Recommendations 1985). Eur. J. Biochem., 159 to its migration order in a certain chromatographic (1986) 1±6; J., 3 (1986) 123±134; J. system [13]. Biol Chem., 262 (1987) 13±18; Pure Appl. Chem.,60 Though these designations are far from being (1988) 1389±1394; Royal Society of Chemistry systematic, and it is impossible to derive the struc- Specialist Periodical Report, Amino Acids and ture from them, they have the advantage of being Peptides, 21, (1990) 329. short and well understood since they have been in [3] IUPAC-IUB Joint Commission on Biochemical use for a long time. A list of these abbreviations is Nomenclature (JCBN). Abbreviated terminology of oligosaccharide chains (Recommendations given in Table 3. 1980). Eur. J. Biochem., 126 (1982) 433±437; J. Since there is no clear-cut system in these abbre- Biol. Chem., 257 (1982) 3347±3351; Pure Appl. viations, it is not recommended to extend the list Chem., 54 (1982) 1517±1522; Arch. Biochem. Bio- by coining new symbols of this kind. As a result, phys., 220 (1983) 325±329. the following two cases are examples of abbrevia- [4] IUPAC-IUBMB Joint Commission on Biochemical tions that should not be used. Nomenclature (JCBN). Nomenclature of carbohy- drates (Recommendations 1996). Pure Appl. Chem., 1. A disialoganglioside, Neu5Ac 3Gal 3(Neu5 68 (1996) 1919±2008; Carbohydr. Res., 297 (1997) 1± Ac 6)GalNAc 4Gal 4GlcCer, has been abb- 90; Adv. Carbohydr. Chem. Biochem., 52 (1997) 43± reviated GD1 . This practice should be 177; J. Carbohydr. Chem., 16 (1997) 1191±1280. discontinued. The recommended abbreviation [5] W.L. Roberts, S. Santikarn, V.N. Reinhold, and for this compound is IV3- -Neu5Ac,III6- - T.L. Rosenberry, J. Biol. Chem., 263 (1988) 18776± 18784. Neu5Ac-Gg Cer. 4 [6] C.C. Sweeley, and B. Siddiqui, in M.I. Horowitz,. 2. The system has been extended to gangliosides and W. Pigman (Eds.), The Glycoconjugates, vol. 1, of other ``root'' types, such as those derived Academic Press, New York, (1977) pp 459±540. from lactotetraosylceramide. An example of [7] G. Reuter and R. Schauer, Glycoconjugate J.,5 this kind is the widely distributed (1988) 133±135. called sialoparagloboside, Neu5Ac 3Gal 4 [8] Nomenclature Committee of IUB (NC-IUB). GlcNAc 3Gal 4GlcCer, which has at times Numbering of atoms in myo-inositol (Recommen- Nomenclature of glycolipids/Carbohydrate Research 312 (1998) 167±175 175

dations 1988). Biochem. J., 258 (1989) 1±2; Eur. J. [11] M.G. Low, and A.R. Saltiel, Science, 239 (1988) Biochem., 180 (1989) 485±486. 268±275. [9] IUPAC-IUB Joint Commission on Biochemical [12] M.A.J. Ferguson, and A.F. Williams, Annu. Rev. Nomenclature (JCBN). Conformational nomen- Biochem., 57 (1988) 285±320. clature for ®ve- and six-membered ring forms of [13] L. Svennerholm, J. Neurochem., 10 (1963) 612±623. monosaccharides and their derivatives (Recom- [14] H. Wiegandt, in A. Neuberger and L.L.M. van Dee- mendations 1980). Eur. J. Biochem., 111 (1980) nen (Eds.), Glycolipids, New Comprehensive Bio- 295±298; Arch. Biochem. Biophys., 207 (1981) 469± chemistry, vol 10, Elsevier, New York, (1985) p 28. 472; Pure Appl. Chem., 53 (1981) 1901±1905. [15] S. Hakomori, in J.N. Kanfer, and S. Hakomori [10] IUPAC-IUB Joint Commission on Biochemical (Eds.), Handbook of Lipid Research, vol. 3. Plenum Nomenclature (JCBN). Symbols for specifying Press, New York and London (1983) pp. 1±165. the conformation of polysaccharide chains [16] C.L.M. Stults, C.C. Sweeley, and B.A. Macher, (Recommendations 1981). Eur. J. Biochem.,131 Methods Enzymol., 179 (1989) 167±214; see also (1983) 5±7; Pure Appl. Chem., 55 (1983) 1269± B.A. Macher, and C.C. Sweeley, Methods Enzy- 1272. mol., 50 (1978) 236.