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Varki A, Cummings RD, Esko JD, et al., editors. Essentials of Glycobiology [Internet]. 4th edition. Cold Spring Harbor (NY): Cold Spring Harbor Laboratory Press; 2022.

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Essentials of Glycobiology [Internet]. 4th edition.

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Gene locus comprising three major allelic glycosyltransferases that generate the A, B, and O blood groups.


An organic compound derived from a hemiacetal by reaction with an alcohol. If the hemiacetal is a sugar, the acetal is a glycoside.


A protein on the surface of bacteria, viruses, or parasites that binds to a ligand present on the surface of a host cell.


A measure of the strength of interaction between a receptor and its ligand.


The clumping of cells in the presence of a protein (e.g., antibody or lectin). The related term hemagglutination denotes the specific case wherein the cells are red blood cells.


Non-carbohydrate portion of a glycoconjugate or glycoside that is glycosidically linked to the glycan through the reducing terminal sugar.


A monosaccharide with an aldehyde group or potential aldehydic carbonyl group (by definition, this is the C-1 position).

Amino sugar

A monosaccharide in which a hydroxyl group is replaced by an amino group.

Anomeric carbon

The carbon atom of a monosaccharide that bears the hemiacetal functionality (C-1 for most sugars; C-2 for sialic acids).


Stereoisomers of a monosaccharide that differ only in configuration at the anomeric carbon of the ring structure.


A branch of an oligosaccharide emanating from a “core” structure.



Asparagine-linked oligosaccharide


Automated glycan assembly

Rapid method for the chemical synthesis of oligo- and polysaccharides on a solid support.


A measure of the combined strength of interaction from the multiple affinities of a multivalent complex.


A functional group comprising three nitrogen atoms bound in a linear arrangement (N3).

Azido sugar

A monosaccharide to which an azido group has been introduced synthetically.



Beta elimination

The cleavage of a C-O or C-N bond positioned on the beta carbon with respect to a carbonyl group. The process is used to cleave O-glycans from Ser or Thr residues.


Community of bacteria that adheres to a moist surface (e.g., surface of ponds or teeth).

C-type lectins

A class of Ca++-dependent lectins recognizable by a characteristic sequence comprising their carbohydrate recognition domain.


Membrane-bound protein chaperone that mediates quality control of protein folding in the endoplasmic reticulum.


Soluble protein chaperone that recognizes N-glycans and mediates quality control of glycoprotein folding in the endoplasmic reticulum.

Capillary electrophoresis (CE)

An analytical technology using high voltage across the span of a small-diameter capillary to accomplish separation. It is applicable to small quantities of carbohydrates and can interface with a mass spectrometer.


A protective extracellular polysaccharide coat surrounding certain bacteria. Presence of a capsular polysaccharide is often associated with virulence.


A generic term used interchangeably in this book with sugar, saccharide, or glycan. Includes monosaccharides, oligosaccharides, and polysaccharides, as well as derivatives of these compounds.

Carbohydrate-recognition domain (CRD)

The domain of a polypeptide that is specifically involved in binding to carbohydrate; in lectins, often a highly evolutionarily conserved region of the polypeptide.

CAZy database

Denoting “Carbohydrate Active enZYmes,” this database describes the families of structurally related catalytic and carbohydrate-binding modules (or functional domains) of enzymes that degrade, modify, or create glycosidic bonds.


A repeating homopolymer of β1-4-linked glucose residues, which is the main constituent of plant cell wall of green plants and many forms of algae and oomycetes and is produced by some bacteria.


The common lipid component of glycosphingolipids, composed of a long-chain amino alcohol (sphingosine) and an amide-linked fatty acid.


A glycolipid composed of ceramide with an attached galactose (galactosylceramide) or glucose (glucosylceramide).

Chemical shift

A term referring to the position of a resonance in an NMR spectrum.

Chemoenzymatic synthesis

Glycan synthesis that uses both chemical and enzymatic reactions to obtain the desired product.


A repeating homopolymer of β1-4-linked N-acetylglucosamine residues; the main component of the cell walls of fungi and the exoskeletons of arthropods, among other functions.

Chondroitin sulfate

A type of glycosaminoglycan defined by the disaccharide unit (GalNAcβ1-4GlcAβ1-3)n, modified with ester-linked sulfate at certain positions and typically found covalently linked to a proteoglycan core protein.

Congenital disorder of glycosylation

An inheritable genetic disorder in which mutations have led to improper assembly of glycans.

Conjugate vaccine

A vaccine consisting of an antigen (frequently a glycan) coupled to a carrier protein.

Coupling correlated spectroscopy (COSY)

An NMR technique producing a two-dimensional map of connections, usually between vicinal protons. Useful in assignment of spectra and identification of carbohydrate residues.

Cryo-electron microscopy (cryo-EM)

An imaging technique capable of providing near-atomic level resolution for three-dimensional structures of proteins and glycoproteins in frozen noncrystalline preparations.

Deoxy sugar

A monosaccharide in which a hydroxyl group is replaced by a hydrogen atom.

Dermatan sulfate

A modified form of chondroitin sulfate in which a portion of the D-glucuronate residues are epimerized to L-iduronates.


A terminally saturated polyisoprenoid lipid carrier utilized during the assembly of N-glycans and GPI anchors and the O- and C-mannosylation of proteins in the endoplasmic reticulum.

Electron transfer dissociation (ETD)

A mass spectrometry fragmentation and ionization technique useful in determining sites of glycosylation on peptides and proteins.

Electrospray ionization (ESI)

A commonly used method for producing charged species for mass spectrometry analysis.


An enzyme that catalyzes the cleavage of an internal glycosidic linkage in an oligosaccharide or polysaccharide.



Epidermal growth factor (EGF)-like repeats

Small protein motifs (∼40 amino acids) with six conserved cysteine residues that form three disulfide bonds. Certain EGF repeats may contain sites for glycan modification.


An enzyme that catalyzes racemization of a chiral center in a sugar.


Two isomeric monosaccharides differing only in the configuration of a single chiral carbon. For example, mannose is the C-2 epimer of glucose.


The part of a molecule that is recognized by a specific antibody or receptor.


A circulating glycosylated cytokine used to treat anemias.


An enzyme that cleaves a monosaccharide from the outer (nonreducing) end of an oligosaccharide, polysaccharide, or glycoconjugate.


Heat-labile, proteinaceous toxins secreted by bacteria that cause illness.

Expressed protein ligation (EPL)

A method for generating semisynthetic proteins by the condensation of a synthetic peptide and a recombinant protein. Glycoproteins can be generated by condensation of a synthetic glycopeptide and a recombinant protein.

Extracellular matrix

A complex array of secreted molecules including glycoproteins, proteoglycans, and/or polysaccharides and structural proteins. In plants, the extracellular matrix is also referred to as the cell wall.

Extrinsic glycan-binding proteins

Receptors that recognize glycans from a different organism and consist mostly of pathogenic microbial adhesins, agglutinins, or toxins.


Proteinaceous fiber-like appendages found in many Gram-negative bacteria.

Fischer projection

A two-dimensional representation of a three-dimensional organic molecule devised by Hermann Emil Fischer.

Fluorophore-assisted carbohydrate electrophoresis (FACE)

A technology that combines glycan derivatization and gel electrophoresis for the analysis of small quantities of carbohydrates.


A synthetic heparin (also called Arixtra) used as an anticoagulant.


Family of proteins that modify Notch activity by catalyzing the transfer of N-acetylglucosamine from UDP-GlcNAc to fucose on an EGF-like repeat.


Five-membered (four carbons and one oxygen, i.e., an oxygen heterocycle) ring form of a monosaccharide named after the structurally similar compound furan.


S-type (sulfhydryl-dependent) β-galactoside-binding lectins, usually occurring in a soluble form, expressed by a wide variety of animal cell types and distinguishable by the amino acid sequence of their carbohydrate recognition domains.


Anionic glycosphingolipid containing one or more residues of sialic acid.

Gene chip

A DNA microarray used to quantify transcript levels in high-throughput format.


The complete genetic sequence of one set of chromosomes.


A generic term for any sugar or assembly of sugars, in free form or attached to another molecule, used interchangeably in this book with saccharide or carbohydrate.

Glycan array

A collection of glycans attached to a surface in a spatially determined manner.

Glycan-binding protein

Protein that recognizes and binds to specific glycans. SeeNEWLINELectin and Glycosaminoglycan-binding protein.


The nonenzymatic, chemical modification of proteins by addition of carbohydrate, usually through a Schiff-base reaction with the amino group of the side chain of lysine and subsequent Amadori rearrangement to give a stable conjugate. Not to be confused with (enzymatic) glycosylation.


Study of the structure, chemistry, biosynthesis, and biological functions of glycans and their derivatives.


Altering the biosynthetic machinery for glycosylation in a given cell for the production of defined glycans on glycoconjugates.


The cell coat consisting of glycans and glycoconjugates surrounding animal cells that is seen as an electron-dense layer by electron microscopy.


A molecule in which one or more glycan units are covalently linked to a noncarbohydrate entity.


Different molecular forms of a glycoprotein, resulting from variable glycan structures at one or more sites of glycosylation and/or differences in the occupancy of glycosylation sites.


A polysaccharide comprising α1-4- and α1-6-linked glucose residues that functions in short-term energy storage in animals; sometimes referred to as animal starch.


A protein that acts as a primer for glycogen synthesis.


General term denoting a molecule containing a saccharide linked to a lipid aglycone. In “higher” organisms, most glycolipids are glycosphingolipids, but glycoglycerolipids and other types exist.


The total collection including a glycon of glycans synthesized by a cell, tissue, or organism under specified conditions of time, space, and environment.


Systematic analysis of the glycome.


Noncarbohydrate compounds that mimic the properties of saccharides.


Carbohydrate component of a glycoconjugate.


A peptide having one or more covalently attached glycan.


A protein with one or more covalently bound glycans.


The systems-level analysis of glycoproteins, including their protein identities, sites of glycosylation, and glycan structures.


Polysaccharide side-chains of proteoglycans or free complex polysaccharides composed of linear disaccharide repeating units, each composed of a hexosamine and a hexose or a hexuronic acid (seeNEWLINEHeparin, Heparan sulfate, Chondroitin sulfate, Dermatan sulfate, Keratan sulfate, and Hyaluronan).

Glycosaminoglycan-binding protein

Protein that recognizes and binds to specific glycosaminoglycans.


An enzyme that catalyzes the hydrolysis of glycosidic bonds in a glycan. See Exoglycosidase and Endoglycosidase.


A glycan containing at least one glycosidic linkage to another glycan or an aglycone.

Glycosidic linkage

Linkage of a monosaccharide to another residue. The linkage generally results from the reaction of a hemiacetal with an alcohol (e.g., a hydroxyl group on another monosaccharide or amino acid) to form an acetal. Glycosidic linkages between two monosaccharides have defined regiochemistry and stereochemistry.


Glycolipid containing a glycan glycosidically attached to the primary hydroxyl group of ceramide.

Glycosyl acceptor

The nucleophile in a glycosylation reaction, usually containing a free hydroxyl group.

Glycosyl donor

The electrophile in a glycosylation reaction; the nucleotide sugar in an enzymatic glycosylation reaction.


The enzyme-catalyzed covalent attachment of a carbohydrate to a polypeptide, lipid, polynucleotide, carbohydrate, or other organic compound, generally catalyzed by a glycosyltransferase, utilizing a specific nucleotide sugar donor.

Glycosylphosphatidylinositol (GPI) anchor

A membrane anchor that consists of a glycan bridge between phosphatidylinositol and a phosphoethanolamine in amide linkage to the carboxyl terminus of a protein.


Enzyme that catalyzes transfer of a sugar from a nucleotide sugar or sugar-phosphate lipid donor to a substrate.


Any small molecule, including a glycan, that is recognized by a receptor or antibody.

Haworth projection

A representation of monosaccharides wherein the cyclic structures are depicted as planar rings with the hydroxyl groups orientated above or below the plane of the ring.


The clumping of red blood cells in the presence of a protein (e.g., antibody or lectin).


A lectin that recognizes carbohydrates on the surface of red blood cells and causes hemagglutination.


A compound formed by reaction of an aldehyde with an alcohol group, as in ring closure of an aldose.


A compound formed by reaction of a ketone with an alcohol group, as in ring closure of a ketose.

Heparan sulfates

Glycosaminoglycans defined by the disaccharide unit (GlcNAcα1- 4GlcAβ1-4/IdoAα1-4)n, containing N- and O-sulfate esters at various positions, and typically found covalently linked to a proteoglycan core protein.


A type of heparan sulfate made by mast cells that has the highest amount of iduronic acid and of N- and O-sulfate residues. Heparin binds and activates antithrombin.

Heteronuclear single quantum coherence (HSQC)

An NMR technique producing a two-dimensional map correlating chemical shifts of heteronuclei (usually 13C for carbohydrates) and chemical shifts of directly bonded protons.


A polysaccharide containing more than one type of monosaccharide.


Hexose with an amino group in place of the hydroxyl group at the C-2 position. Common examples found in vertebrate glycans are the N-acetylated sugars, N-acetylglucosamine and N-acetylgalactosamine.


A 6-carbon monosaccharide typically with an aldehyde (or potential aldehyde) at the C-1 position (aldohexose) and hydroxyl groups at all other positions. Common examples in vertebrate glycans are mannose, glucose, and galactose.

High pressure liquid chromatography (HPLC)

A separation technique frequently used to isolate glycans for analysis or subsequent study.


A polysaccharide composed of only one type of monosaccharide.


A glycosaminoglycan defined by the disaccharide unit (GlcNAcβ1-4GlcAβ1-3)n that is neither sulfated nor covalently linked to protein; referred to in older literature as hyaluronic acid.


A chemical method that uses hydrazine to cleave amide bonds (e.g., the glycosylamine linkage between a sugar residue and asparagine or the acetamide bond in N-acetylhexosamines).

I-type lectins

A class of lectins belonging to the immunoglobulin superfamily.

Intrinsic glycan-binding proteins

Receptors that recognize glycans from the same organism. Typically they mediate cell–cell interactions or recognize extracellular molecules, but they can also recognize glycans on the same cell.

Jelly-roll fold

Description of tertiary structure common to L-type lectins.

Keratan sulfate

A polylactosamine [Galβ1-4GlcNAcβ1-3]n with sulfate esters at C-6 of N-acetylglucosamine and galactose residues, found in a keratan sulfate proteoglycan.


An organic compound derived from a hemiketal by reaction with an alcohol. If the hemiketal is a sugar, the ketal is a glycoside.


A monosaccharide with a ketone group or a potential ketonic carbonyl group (typically at the C-2 position in natural compounds).

L-type lectins

Superfamily of glycan-binding proteins with a common feature of tertiary structure called a “jelly-roll” fold.


The disaccharide Galβ1-4Glc; an abundant milk sugar.


A protein (other than an anticarbohydrate antibody) that specifically recognizes and binds to glycans without catalyzing a modification of the glycan.

Lewis blood group antigens (e.g., Lex, Ley, and Lea)

A related set of glycans that carry α1-3/1-4 fucose residues covalently linked to galactose or N-acetylglucosamine.


A molecule that is recognized by a specific receptor. In the case of lectins, the ligands are partly or completely glycan-based.

Link module

A protein fold that interacts specifically with hyaluronan.

Linkage analysis

A technology employing a combination of derivatization of hydroxyl groups, gas chromatography (GC) separation, and mass spectrometry to identify types between monosaccharides in a glycan.

Lipid A (also known as endotoxin)

Lipid that contains fatty acids linked to glucosamine with a variable number of phosphate groups and 1–4 units of ketodeoxyoctulosonic acid (Kdo). SeeNEWLINELipopolysaccharide.

Lipid-linked oligosaccharide (LLO)

An oligosaccharide linked to dolichol or lipid.

Lipid rafts

Small lateral microdomains of self-associating membrane molecules.

Lipooligosaccharide (LOS)

Similar to lipopolysaccharide but lacking the O-antigen polysaccharide side chain repeats.

Lipopolysaccharide (LPS)

A bacterial glycolipid composed of a polysaccharide (O-antigen), connected via a core oligosaccharide to lipid A that makes up the major portion of the outer leaflet of the outer membrane of Gram-negative bacteria. A major determinant of antigenic specificity, also known as heat-stable toxin or endotoxin.

Lysosomal storage disorder

Human genetic disorder in which a defect in a lysosomal enzyme results in the accumulation of undigested glycoconjugates in the lysosomes (e.g., Tay–Sachs disease).


An endo-β-N-acetylhexosaminidase that cleaves the polysaccharide backbone of bacterial peptidoglycan.


Mannose-rich polysaccharide found in certain bacteria, fungi, and plants.

Mannose 6-phosphate receptors

SeeNEWLINEP-type lectins.

Mass spectrometry (MS)

An analysis technique providing the mass of ionizable glycans and their fragments in the gas phase. The small sample amounts required make it particularly useful for glycan analysis.

Matrix-assisted laser desorption/ionization (MALDI)

A procedure commonly used to produce charged species for mass spectrometric analysis.

Membrane-derived oligosaccharides (MDOs)

Highly charged β-glucans that create an osmotic buffer in the periplasmic space of Gram-negative bacteria.

Metabolic labeling

A procedure dependent on metabolic processes in cells to incorporate isotopic or derivatized monosaccharides (or other moieties) into glycans for subsequent analysis.

Methylation analysis

A method for carbohydrate structure analysis based on the acid stability of methyl ethers and the acid lability of glycosidic linkages; used to determine the linkage positions of monosaccharide residues in an oligosaccharide chain.

Michael addition

The chemical reaction in which a nucleophile attacks the β carbon of an α,β-unsaturated carbonyl compound. The reaction is used after O-glycan β elimination in order attach probes to those sites.


A collection of molecules (e.g., DNA, proteins, or glycans) spatially arrayed on a surface with micrometer dimensions.


Structural variations in a glycan at any given glycosylation site on a protein (microheterogeneity generates glycoforms).

Molecular mimicry

Strategy some microbial pathogens use to evade immune reactions by decorating themselves with glycans similar to their hosts.

Molecular dynamics (MD)

A computational technique based on Newton's laws of motion useful in simulating motions and structures of glycans or glycan–protein complexes.

Molecular docking

A computational technique useful in predicting binding sites and geometry for glycan–protein complexes.


Carbohydrate that cannot be hydrolyzed into a simpler carbohydrate. The building block of oligosaccharides and polysaccharides. Simple monosaccharides are polyhydroxyaldehydes or polyhydroxyketones with three or more carbon atoms.


Large glycoprotein with a high content of serine, threonine, and proline residues and numerous O-GalNAc glycans, often occurring in clusters on the polypeptide.


An out-of-date term replaced by the term, glycosaminoglycan. Still used as a group name for human disorders (“mucopolysaccharidoses”) involving glycosaminoglycan accumulation due to genetic deficiency of certain lysosomal enzymes.


The interconversion of stereoisomers at the anomeric center of a monosaccharide.


Having multiple points of interaction. Often seen in oligomeric lectins in which low affinity individual interactions combine to provide high avidity.


A disaccharide with the sequence Galβ1-4GlcNAc.

N-glycan (N-linked oligosaccharide, N-linked glycan)

Glycan covalently linked to the side-chain amide of asparagine residue of a polypeptide chain in the consensus sequence: -Asn-X-Ser/Thr. Unless otherwise stated, the term N-glycan is used generically in this book to denote the most common linkage region, Manβ1-4GlcNAcβ1-4GlcNAcβ1-N-Asn.

Native chemical ligation

(NCL) A technique used to generate large polypeptides by condensation of smaller peptide fragments.



Nod factor

Lipooligosaccharide produced by Rhizobium bacteria that stimulates nodule formation and initiates nitrogen fixation in leguminous plants.

Nonreducing terminus (nonreducing end)

Outermost end of an oligosaccharide or polysaccharide chain, opposite to that of the reducing end.


Family of cell-surface receptors that are glycosylated on EGF-like repeats. Ligands include Delta and Serrate/Jagged.

Nuclear magnetic resonance (NMR)

A spectroscopic technique based on detecting precession of magnetically active nuclei in strong magnetic fields. Useful in structure determination of both glycans and protein–glycan complexes as they exist in solution.

Nuclear Overhauser effect (NOE)

An effect on intensities of resonances in NMR spectra that is often related to inter- nuclear distances in the case of proton–proton experiments.

Nucleotide sugar

Activated form of monosaccharide, such as UDP-Gal, GDP-Fuc, and CMP-Sia, typically used as a donor substrate by glycosyltransferases.

Nucleotide sugar transporter

Membrane-bound protein that specifically transports nucleotide sugars from the cytosol into the lumen of intracellular organelles (e.g., the Golgi).

O-GalNAc glycan



Dynamic modification of proteins by β-linked N-acetylglucosamine (a posttranslational modification often reciprocal with protein phosphorylation).

O-glycan (O-linked oligosaccharide, O-linked glycan)

A glycan glycosidically linked to the hydroxyl group of the amino acid serine, threonine, tyrosine, or hydroxylysine. Unless otherwise stated, the term O-glycan is used in this book to denote the common linkage GalNAcα1-O-Ser/Thr.


Linear or branched chain of monosaccharides attached to one another via glycosidic linkages. The number of monosaccharide units can vary; the term polysaccharide is usually reserved for large glycans with repeating units.


A bacterial polysaccharide consisting of MurNAcβ1-4GlcNAcβ1-4 repeat units, covalently cross-linked to short peptides. Also known as murein, peptidoglycan represents the major structural component of the periplasm.

Periodate oxidation

A reaction using periodate to cleave C–C bonds with vicinal hydroxyl groups (e.g., within carbohydrates) to form the two corresponding aldehydes.

Pili (Fimbriae)

Hair-like appendages on the surface of some bacteria that often contain adhesins.


A lipid polymer composed of repeating units of the unsaturated 5-carbon isoprene unit. SeeNEWLINEDolichol and Undecaprenol.


Repeating units of N-acetyllactosamines [Galβ1-4GlcNAcβ1-3]n, of variable length (sometimes called PolyLacNAc).

Polymerase chain reaction (PCR)

The process used to amplify DNA starting from a template DNA strand and complementary oligonucleotide primers.


Glycan composed of repeating monosaccharides, generally greater than ten monosaccharide units in length.

Polysialic acid

A homopolymer of sialic acids abundant in the brain and fish eggs and found on certain pathogenic bacteria.

Protecting group

A chemical moiety commonly used in glycan synthesis that masks hydroxyl groups in order to prevent them from reacting with other chemical reagents.

Protein data bank (PDB)

A repository containing atomic coordinates primarily for proteins, but also nucleic acids and protein-carbohydrate complexes. Each entry is given a four-element alpha-numeric code.


Any protein with one or more covalently attached glycosaminoglycan chains.


The total collection of proteins in a cell, tissue, or organism, under specific conditions of time, space, and environment.

P-type lectins

Class of lectins that recognize mannose-6-phosphate (also called M6P receptors).

Pulsed amperometric detection

A detection procedure based on conduction at high pH and used in HPLC analysis of monosaccharide composition.


Six-membered (five carbons and one oxygen, i.e., an oxygen heterocycle) ring form of a monosaccharide; the most common form found for hexoses and pentoses. The name is based on the structural similarity to the compound “pyran.”

R-type lectins

Superfamily of glycan-binding proteins that contain a carbohydrate-recognition domain similar to that in ricin.


A protein that binds to a ligand and initiates signal transmission or other cellular activity. In this book, most receptors are lectins (i.e., they recognize glycans). In microbiology, adhesins or agglutinins on the microbes bind to receptors which are glycans on the host cell.

Reducing terminus (reducing end)

End of a glycan that has reducing power because it is unattached to an aglycone and is thus a hemiacetal. In a glycoconjugate, reducing terminus is also used as a synonym for a potential reducing terminus, referring to the end of a glycan covalently attached to the aglycone by a glycosidic bond (i.e., it would have reducing power if it were released).


The region among many possible regions of a molecule that is involved in a chemical reaction. For glycosidic linkages, regiochemistry denotes the hydroxyl group of one monosaccharide that is bound to the anomeric position of the other (i.e., 1-3 vs. 1-4 linkage).

S-layer (surface-layer)

A protein monolayer coating often containing covalently linked glycans and found in the cell envelope of many bacteria and archea.


A generic term for any carbohydrate or assembly of carbohydrates, in free form or attached to another molecule, used interchangeably in this book with carbohydrate and glycan.


A glycoconjugate comprising fatty acyl chains covalently attached directly to a sugar backbone (e.g., Lipid A).

Saturation transfer difference (STD)

An NMR technique useful in detecting protein–glycan binding and identifying parts of glycans in close approach to protons in the binding sites of protein receptors.


A C-type (Ca++-dependent) lectin expressed by cells in the vasculature and bloodstream. The three known selectins are L-selectin/CD62L (expressed by most leukocytes), E-selectin/CD62E (expressed by cytokine-activated endothelial cells), and P-selectin/CD62P (expressed by activated endothelial cells and platelets).

Ser/Thr-linked oligosaccharide


Sialic acids

Family of acidic sugars with a nine-carbon backbone, of which the most common is N-acetylneuraminic acid, in vertebrates.


Enzyme that releases sialic acid residues from a glycoconjugate. Older name was neuraminidase, now used only to refer to the influenza sialidase.


Total array of sialic acid types and linkages expressed by a particular cell tissue or organism, under specified conditions of time, space, and environment.


Sialic acid–binding protein that is a member of the I-type lectin family and has an amino-terminal V-set domain with typical conserved residues.

Single-particle analysis (SPA)

An analysis technique used in some cryo-EM studies that extracts 3D structures from 2D images of randomly oriented objects.

Small-angle X-ray scattering (SAXS)

An X-ray scattering technique useful in defining the shape of large molecular complexes as they exist in solution.


Lipids with ceramide as their core structure.


Long-chain amino alcohol (forms ceramide when in amide linkage with a fatty acid).


A generic term often used to refer to any carbohydrate, but most frequently to low-molecular-weight carbohydrates that are sweet in taste. Table sugar, sucrose, is a nonreducing disaccharide (Fruβ2-1αGlc). Oligosaccharides are sometimes called “sugar chains” and individual monosaccharides in a sugar chain are sometimes referred to as “sugar residues.”

Surface plasmon resonance (SPR)

An optical technique for the measurement of adsorption of materials onto a surface. Frequently used to estimate affinities of proteins for glycans on coated chips.

Teichoic acid

A complex polymer consisting of either phosphoglycerol- or phosphoribitol-carrying carbohydrates or amino acids, found on the surface of Gram-positive bacteria.

Time of flight (TOF)

An analysis technique used in mass spectrometry to separate species of different mass based on velocity differences for particles with equal kinetic energy.

Transfer nuclear Overhauser effect (trNOE)

An NMR technique particularly useful in determining the conformation of glycans noncovalently bound to proteins.

Thrombospondin repeat (TSR)

Small protein motif (50–60 amino acids) with six conserved cysteine residues that form three disulfide bonds. Serves as a site for glycan modification.


The total collection of RNA transcripts in a cell, tissue, or organism, under specific conditions of time, space, and environment.

Undecaprenol (bactoprenol, C55 isoprenoid)

A polyisoprenoid lipid carrier for membrane-bound glycan synthesis in bacteria.

X-ray crystallography

A structure determination technique dependent on scattering of X-rays from molecules ordered in crystals. Useful in the determination of three-dimensional structures of protein–glycan complexes.

Copyright © 2022 by the Consortium of Glycobiology Editors, La Jolla, California. Published by Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York. All rights reserved.

The content of this book is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 Unported license. To view the terms and conditions of this license, visit https://creativecommons.org/licenses/by-nc-nd/4.0/

Bookshelf ID: NBK579967PMID: 35914067


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