Structure and Taste of Some Analogs of Naringin

The structures of acidic oligosaccharides synthesized by a transglycosylation reaction by Bacillus circulans β-galactosidase, using lactose as the galactosyl donor, and N-acetylneuraminic acid (NeuAc) and glucuronic acid (GlcUA) as the acceptors were investigated. Acidic oligosaccharides thus synthesized were purified by anion exchange chromatography and charcoal chromatography. The MS and NMR studies indicated that the acidic oligosaccharides from NeuAc were Galβ-(1→8)-NeuAc, Galβ-(1→9)-NeuAc, and Galβ-(1→3)-Galβ-(1→8)-NeuAc, and those from GlcUA were Galβ-(1→3)-GlcUA and Galβ-(1→4)-Galβ-(1→3)-GlcUA. These are novel acidic galactooligosaccharides.     

Conformational changes due to vicinal glycosylation: The branched α-l-Rhap(1–2)[β-d-Galp(1–3)]-β-d-Glc1-OMe trisaccharide compared with its parent disaccharides*

Conformations of the α-l -Rhap(1-2)-β-d -Glc1-OMe and β-d -Galp(1-3)-β-d -Glc1-OMe disaccharides and the branched title trisaccharide were examined in DMSO-d₆ solution by ¹H-nmr. The distance mapping procedure was based on rotating frame nuclear Overhauser effect (NOE) constraints involving C- and O-linked protons, and hydrogen-bond constraints manifested by the splitting of the OH nmr signals for partially deuteriated samples. An “isotopomer-selected NOE” method for the unequivocal identification of mutually hydrogen-bonded hydroxyl groups was suggested. The length of hydrogen bonds thus detected is considered the only one motionally nonaveraged nmr-derived constraint. Molecular mechanics and molecular dynamics methods were used to model the conformational properties of the studied oligosaccharides. Complex conformational search, relying on a regular Φ,Ψ-grid based scanning of the conformational space of the selected glycosidic linkage, combined with simultaneous modeling of different allowed orientations of the pendant groups and the third, neighboring sugar residue, has been carried out. Energy minimizations were performed for each member of the Φ,Ψ grid generated set of conformations. Conformational clustering has been done to group the minimized conformations into families with similar values of glycosidic torsion angles. Several stable syn and anti conformations were found for the 1→2 and 1→3 bonds in the studied disaccharides. Vicinal glycosylation affected strongly the occupancy of conformational states in both branches of the title trisaccharide. The preferred conformational family of the trisaccharide (with average Φ,Ψ values of 38°, 17° for the 1→2 and 48°, 1° for the 1→3 bond, respectively) was shown by nmr to be stabilized by intramolecular hydrogen bonding between the nonbonded Rha and Gal residues. © 1998 John Wiley & Sons, Inc. Biopoly 46: 417–432, 1998     

Structure of novel glyceroglycolipids in Adzuki bean (Vigna angularis) seeds

In addition to monoglycosyl diacylglycerol, three glyceroglycolipids with two to four hexose units were isolated from Adzuki bean seeds. Their structures were determined using enzymatic hydrolysis, permethylation analysis, nuclear magnetic resonance spectroscopy, and reversed-phase high pressure liquid chromatography, as folows: Gal(beta 1----3')- for the monoglycosyl diacyglycerol, Gal(alpha 1----6)-Gal(beta 1----3')- and Gal(beta 1----6)-Gal(beta1----3')- for the diglycosyl diacylglycerol, [Gal(beta 1----6]2-Gal(beta 1----3')- and Gal(beta 1----6)-Gal(alpha 1----6)-Gal(beta 1----3')- for the triglycosyl diacylglycerol, and [Gal(beta 1----6)]3-Gal(beta 1----3')- and [Gal(beta 1----6)]2-Gal(alpha 1----6)-Gal(beta 1----3')- for the tetraglycosyl diacylglycerol. Except for Gal(alpha 1----6)-Gal(beta 1----3')-diacylglycerol, all of the glycolipids with oligosaccharide moieties had novel glycosidic linkage patterns differing from those in the well-known glyceroglycolipids in nature. The predominant diacylglycerol species component was characterized as dilinolenin. However, the molecular species composition of the diacylglycerol moieties of the two diglycosyl isomers with different glycosidic linkage patterns were found to be qualitatively the same but different quantitatively, as follows: in the well-known isomer Gal(alpha 1----6)-Gal(beta 1----3')-, 39% dilinolenin, 15% palmitoyl linolenin, and 14% linoleoyl linolenin; and in the novel isomer Gal(beta 1----6)-Gal(beta 1----3')-, 35% dilinolenin, 24% dilinolein, and 21% linoleoyl linolenin.     

Solvent-dependent conformational behaviour of lipochitoligosaccharides related to Nod factors.

The solution conformation of two lipooligosaccharides related to Nod factors or lipochitoligosaccharides have been analysed by 1D and 2D 1H and 13C NMR spectroscopy, molecular mechanics and dynamics calculations. The obtained data indicate that the glycosidic torsion angles have restricted fluctuations, but may adopt a variety of shapes. Remarkably, the relative orientation of the fatty acid chain towards the oligosaccharide backbone is solvent dependent. In water solution, the acyl residue and the oligosaccharide adopt a quasi-parallel orientation for a significant amount of time.     

Conformational analysis of a dinucleotide photodimer with the aid of the genetic algorithm.

The solution structure of the photodimer cis,syn-dUp[]dT is derived with the aid of the genetic algorithm. The conformational space available for the molecule is sampled efficiently using the computer program DENISE and tested against a set of constraints available from nmr experiments. The dominant conformation in solution found with this approach can be described by the following combinations of sugar-phosphate backbone torsion angles: epsilon(t), zeta(t), alpha(+), beta(-ac), and gamma(t). The conformation of the sugars and glycosidic torsion angles are S type and syn, respectively. The cyclobutane ring and pyrimidines are puckered. In addition, other conformations that exist in equilibrium with the first are found. It is concluded that the cyclobutane-pyrimidine system is rigid, whereas the sugar-phosphate backbone is flexible. The solution structures are compared with the crystal structure of the strongly related cyano-ethyl ester of cis,syn-dTp[]dT.     

Solution dynamics of the oligosaccharide moiety of ganglioside GM1: Comparison of solution conformations with the bound state conformation in association with cholera toxin B-pentamer

The solution dynamics of the oligosaccharide moiety of ganglioside G_M1 have been determined by use of a combination of ¹H rotating frame Overhauser effect measurements and restrained molecular dynamics simulations, It is found that the Galβ1-3 and NeuNAc moieties which are primarily recognized by cholera toxin both exhibit considerable torsional flexibility about their respective glycosidic linkages. A comparison with the bound state conformation of the ganglioside in association with cholera toxin B-pentamer, shows that a low energy conformation of the oligosaccharide, which closely approximates the globel minimum, is selected upon binding.     

Enzymatic fragmentation of carbohydrate moieties of radish arabinogalactan-protein and elucidation of the structures

We investigated the structures of L-arabino-galactooligosaccharides released from the sugar moieties of a radish arabinogalactan-protein (AGP) by the action of exo-β-(1→3)-galactanase. We detected a series of neutral β-(1→6)-linked galactooligosaccharides forming branches of one to up to at least 19 consecutive Gal groups, together with corresponding acidic derivatives terminating in 4-O-methyl-glucuronic acid (4-Me-GlcA) at the non-reducing end. Some oligosaccharide chains of degree of polymerization (dp) higher than 3 for neutral, and 4 for acidic oligomers were modified with L-Araf residues. The acidic tetrasaccharide 4-Me-β-GlcA-(1→6)[α-L-Araf-(1→3)]-β-Gal-(1→6)-Gal was detected as an abundant L-Araf-containing oligosaccharide among these neutral and acidic oligomers. A pentasaccharide containing an additional L-Araf group attached to the L-Ara in the tetrasaccharide through an α-(1→5)-linkage was also found. We observed L-arabino-galactooligosaccharides substituted with single or disaccharide L-Araf units at different Gal residues along these neutral and acidic β-(1→6)-galactooligosaccharide chains, indicating that these side chains are highly variable in length and substituted variously with L-Araf residues.     

The asparagine-linked sugar chains of the glycoproteins in rat erythrocyte plasma membrane—Fractionation of oligosaccharides liberated by hydrazinolysis and structural studies of the neutral oligosaccharides

The asparagine-linked sugar chains of the plasma membrane glycoproteins of rat erythrocytes were released as oligosaccharides by hydrazinolysis and labeled by NaB³H₄ reduction. The radioactive oligosaccharides were separated into a neutral and at least four acidic fractions by paper electrophoresis. The neutral oligosaccharide fraction was separated into at least 11 peaks upon Bio-Gel P-4 column chromatography. Structural studies of them by sequential exoglycosidase digestion in combination with methylation analysis revealed that they were a mixture of three high mannose-type oligosaccharides and at least 11 complex type oligosaccharides with Manα1 → 6(Manα1 → 3)Manβ1 → 4GlcNAcβ1 → 4(±Fucα1 → 6)GlcNAc as their cores and Galβ1 → 4GlcNAc, Galβ1 → 3Galβ1 → 4GlcNAc, and various lengths of Galβ1 → 4GlcNAc repeating chains in their outer chain moieties. Most of the complex-type Oligosaccharides were biantennary, and the tri- and tetraantennary Oligosaccharides contain only the Galβ1 → 3Galβ1 → 4GlcNAc group in their outer chain moieties.     

The asparagine-linked sugar chains of the glycoproteins in rat erythrocyte plasma membrane—Structural studies of the acidic oligosaccharides

Among the four acidic oligosaccharide fractions obtained by paper electrophoresis of the hydrazinolysate of the plasma membrane glycoproteins of rat erythrocytes, one was further separated into two by prolonged paper electrophoresis using 120-cm paper. Three fractions were mixtures of monosialyl oligosaccharides and two of disialyl oligosaccharides. After desialylation, their neutral portions were fractionated by Bio-Gel P-4 column chromatography and by affinity chromatography using a Con A-Sepharose column. Structural studies of the neutral oligosaccharides, thus obtained, indicated that at least 26 different complex-type oligosaccharides are present as a neutral portion of the acid oligosaccharides. Structurally they can be classified into bi-, tri-, and tetraantennary oligosaccharides with Manα1 → 6(Manα1 → 3)Manβ1 → 4GlcNAcβ1 → 4(±Fucα1 → 6)GlcNAc_OT as their common cores. Galβ1 → 3Galβ1 → 4GlcNAc, Siaα2 → 3Galβ1 → 4GlcNAc, Siaα2 → 6Galβ1 → 4GlcNAc, and a series of Siaα2 → (Galβ1 → 4GlcNAcβ1 → 3)_n · Galβ1 → 4GlcNAc were found as their outer chains. Their structures together with the structures of neutral oligosaccharides reported in the preceding paper indicated that the outer chain moieties of the asparagine-linked sugar chains of rat erythrocyte membrane glycoproteins are formed not by random concerted action of glycosyl transferases in Golgi membrane but by the mechanism in which the formation of one outer chain will regulate the elongation of others.     

Different asparagine-linked sugar chains on the two polypeptide chains of human chorionic gonadotropin

Human chorionic gonadotropin (hCG) purified from placenta, like urinary hCG, is shown to have the sialylated forms of three neutral oligosaccharides: Galβ1→4GlcNAcβ1→2Manα1→6(Galβ1→4GlcNAcβ1→2Manα1→3)Manβ1→4GlcNAcβ1→4(Fucα1→6)GlcNAc (N-1), Galβ1→4GlcNAcβ1→2Manα1→6(Galβ1→4GlcNAcβ1→2Manα1→3)Manβ1→4GlcNAcβ1→4GlcNAc (N-2) and Manα1→6(Galβ1→4GlcNAcβ1→2Manα1→3)Manβ1→4GlcNAcβ1→4GlcNAc (N-3). Gel permeation chromatographic analysis of oligosaccharides released from α- and β-subunits of placental hCG has revealed that the α-subunit has one each of sialylated N-2 and N-3, while the β-subunit has one each of sialylated N-1 and N-2.     

NMR investigations of protein–carbohydrate interactions: insights into the topology of the bound conformation of a lactose isomer and β-galactosyl xyloses to mistletoe lectin and galectin-1

A hallmark of oligosaccharides is their often limited spatial flexibility, allowing them to access a distinct set of conformers in solution. Viewing each individual or even the complete ensemble of conformations as potential binding partner(s) for lectins in protein–carbohydrate interactions, it is pertinent to address the question on the characteristics of bound state conformation(s) in solution. Also, it is possible that entering the lectin’s binding site distorts the low-energy topology of a glycosidic linkage. As a step to delineate the strategy of ligand selection for galactosides, a common physiological docking point, we have performed a NMR study on two non-homologous lectins showing identical monosaccharide specificity. Thus, the conformation of lactose analogues bound to bovine heart galectin-1 and to mistletoe lectin in solution has been determined by transferred nuclear Overhauser effect measurements. It is demonstrated that the lectins select the syn conformation of lactose and various structural analogues (Galβ(1→4)Xyl, Galβ(1→3)Xyl, Galβ(1→2)Xyl, and Galβ(1→3)Glc) from the ensemble of presented conformations. No evidence for conformational distortion was obtained. Docking of the analogues to the modeled binding sites furnishes explanations, in structural terms, for exclusive recognition of the syn conformer despite the non-homologous design of the binding sites.     

Binding of synthetic sulfated ligands by human splenic galectin 1, a β-galactoside-binding lectin

The carbohydrate-binding site of galectin 1, a vertebrate β-galactoside-binding lectin, has a pronounced specificity for the βGal(1→3)- and βGal(1→4)GlcNAc sequences. The binding inhibition study reported herein was carried out to determine whether sulfation of saccharides would influence their binding by galectin 1. The presence of 6′-OSO3- on LacNAc greatly reduces the inhibitory potency relative to LacNAc. 3′-OSO3-LacNAc, 3′-OSO3-Galβ(1→3)GlcNAcβ1-OBzl and 3-OSO3-Galβ1-OMe are more potent inhibitors than the non-sulfated parent compounds. Surprisingly, 2′-OSO3-LacNAc showed over 40 fold less inhibitory potency relative to LacNAc. Ovarian carcinoma A121 cells were shown to synthesize sulfated macromolecules that bind to galectin 1. Modulation in vivo of saccharide sulfation may lead to modulation of galectin 1 interaction with glycoconjugates; hence, sulfation could play a role in modulating lectin functions.     

Partial characterization of the acidic oligosaccharides from rat sublingual glycoprotein

Five sialic acid-containing oligosaccharides composed of nine, ten, twelve, thirteen and fifteen sugar residues, respectively, have been isolated from rat sublingual glycoprotein. Each oligosaccharide contained sialic acid, N-acetylglucosamine, N-acetylgalactosaminitol and galactose. The partial structures of desialyzed oligosaccharides, as determined by sequential degradation with specific glycosidases, are proposed to be: GlcNAc→^βGal→^βGlcNAc→^βGal→^βGlcNAc→^βGal→^βGlaNAc→^βGal→^βGlcNAc→^βGalNac-ol (oligosaccharide I), GlcNAc→^βGal→^βGlcNAc→^βGal→^βGlcNAc→^βGal→^βGlcNAc→^βGalNAc-ol (oligosaccharides II and III) and GlcNAc→^βGal→^βGlcNAc→^βGal→^βGlcNAc→^βGalNAc-ol (oligosaccharides IV and V).     

Single helical structure of curdlan triacetate

The molecular and crystal structure of curdlan triacetate, acetylated (1 → 3)β-D -glucan, was analyzed by means of an x-ray diffraction technique with the help of the linked-atom least-squares method. Unit cell dimensions are a = b = 11.00(1), c(fiber axis) = 22.91 (9) Å, and γ = 120°. The space group is P6₁. The unit cell contains six chemical repeating units related by 6/I-helical symmetry, which is essentially the same as the backbone conformation of one of the modifications (form I) of curdlan. During the refinement calculation, the terminal methyl in every acetyl moiety was elastically restrained to the trans conformation commonly observed in related oligosaccharide structures. The difference Fourier map, the observed and calculated densities, and the thermogravimetric measurement indicated one water molecule per glucose residue. The water oxygen is linked to two carbonyl oxygens in adjacent molecules by hydrogen bonds. The conformation of the primary acetyl moiety is a (skew, -gauche, trans). So far, no skew conformation was observed for the primary acetyl and hydroxyl moieties except in α, β-panose. In both cases, the unusual eclipsed orientation of the primary group is attributed to the hydrogen bond and this conformation is quite different from that of pachyman triacetate. © 1996 John Wiley & Sons, Inc.     

Conformation of the oligosaccharide receptor for E-selectin

A tetrasaccharide related to the blood group oligosaccharides, known as sialyl Lewis^X, has been proposed as the receptor for the lectin responsible for leukocyte adhesion named alternatively as E-selectin or ELAM-1. The ¹³C- and ¹H-nmr spectra have been completely assigned for a tetrasaccharide model of this receptor, Neu5Ac α-(2 → 3)-Gal β-(1 → 4)-[ Fuc α-(1 → 3)-] GlcNAc β-NHAc. Quantitative nuclear Overhauser data (NOESY) have been recorded and analyzed by a complete spin matrix simulation method. Conformational space was exhaustively searched and all conformational models whose simulated NOESY spectra matched the experiment were found. Molecular mechanics and molecular dynamics calculations were carried out to test whether the experimental conformations are low energy and thus likely to represent true single conformations for the tetrasaccharide. It was concluded that while the Lewis^X trisaccharide portion of the compound adopts a single conformation, there is likely to be some flexibility about the Neu5Ac α-(2 → 3)-linkage. A model featuring fast exchange between two different conformations of this linkage is found to be consistent with both the nmr experiments and the molecular dynamics simulations. © 1994 John Wiley & Sons, Inc.     

Mannose transfer to lipid linked di-N-acetylchitobiose

Mannose was found to be transferred from guanosine diphosphate mannose to dolichol-P-P-di-N-acetylchitobiose when these substrates were incubated with hen oviduct or rat liver microsomes. The oligosaccharide moiety of the product appears to be the trisaccharide β-mannosyl-β-N-acetylglucosaminyl-(1→4)-N-acetylglucosamine as judged by the action of glycosydases. Under certain conditions further transfer of mannose occurs and larger oligosaccharides bound to lipid are formed.     

Blood group-active carbohydrate chains on the receptor for epidermal growth factor of A431 cells

The antigens expressed on the carbohydrate chains of the receptor for epidermal growth factor of A431 cells were studied by immunoblotting with monoclonal antibodies. Blood group A and the Type 1 based blood group ALeb and Lea antigens were detected as well as antigens associated with unsubstituted, monofucosylated and difucosylated Type 2 blood group chains. The Lea and the difucosylated Type 2 antigen activities were abolished by treating the blotted receptor with endo-beta-galactosidase, indicating that they are expressed on backbone structures of poly-lacto/neolacto type. (The term 'poly-lacto/neolacto' is used here to describe oligosaccharide backbone structures consisting of repeating Type 1, Gal beta 1-3GlcNAc (lacto) or Type 2, Gal beta 1-4GlcNAc (neolacto) sequences.) The glycosidic linkage of oligosaccharides to protein was investigated using Pronase digests of the receptor biosynthetically labelled with [3H]glucosamine or [3H]fucose. The oligosaccharides were alkali-resistant, consistent with N- rather than O-glycosidically linked chains. A proportion of [3H]fucose-labelled glycopeptides was susceptible to endo-beta-galactosidase, confirming the immunoblotting experiment using antibodies against the Lea and the difucosylated Type 2 antigenic determinants. Oligosaccharides were released from the [3H]fucose- and [3H]-glucosamine-labelled glycopeptides by hydrazinolysis. Chromatography of the oligosaccharides on Bio-Gel P6 and Concanavalin A columns indicated a spectrum of oligosaccharides which include those of high mannose type labelled with [3H]glucosamine, and a mixture of oligosaccharides labelled with [3H]fucose and [3H]glucosamine of bi- and multiantennary complex types of which a subpopulation is susceptible to digestion with endo-beta-galactosidase.     

Molecular dynamics simulation of Lewis blood groups and related oligosaccharides.

Molecular dynamics simulations without explicit inclusion of solvent molecules have been performed to study the motions of Lewisa and Lewisb blood group oligosaccharides, and two blood group A tetrasaccharides having type I and type II core chains. The blood group H trisaccharide has also been studied and compared with the blood group A type II core chain. The potential energy surface developed by Rasmussen and co-workers was used with the molecular mechanics code CHARMM. The lowest energy minima of the component disaccharide fragments were obtained from conformational energy mapping. The lowest energy minima of these disaccharide fragments were used to build the tri- and tetrasaccharides that were further minimized before the actual heating/equilibration and dynamics simulations. The trajectories of the disaccharide fragments, e.g., Fuc alpha- (1----4)GlcNAc, Gal beta-(1----4)GlcNAc, etc., show transitions among various minima. However, the oligosaccharides were found to be dynamically stable and no transitions to other minimum energy conformations were observed in the time series of the glycosidic dihedral angles even during trajectories as long as 300 ps. The stable conformations of the glycosidic linkages in the oligosaccharides are not necessarily the same as the minimum energy conformation of the corresponding isolated disaccharides. The average fluctuations of the glycosidic angles in the oligosaccharides were well within the range of +/- 15 degrees. The results of these trajectory calculations were consistent with the relatively rigid single-conformation models derived for these oligosaccharides from 1H-nmr data.     

Measuring the magnitude of internal motion in a complex hexasaccharide

For the development of a scheme for quantitative experimental estimation of internal motion in the complex human milk hexasaccharide lacto‐N‐di‐fuco hexose I (LNDFH I), we measured a large number of experimental residual dipolar couplings in liquid crystal orienting media. We present a total of 40 ¹³C? ¹H and ¹H? ¹H dipolar coupling values, each representing distinct directions of internuclear vectors. The NMR data were interpreted with established methods for analysis of rigid subdomains of the oligosaccharide as well as a novel method in which dipolar couplings were calculated over an ensemble of conformers from a solvent Molecular Dynamics trajectory using multiple linear regression analysis. The Lewis^b epitope region of LNDFH I assumed a single unique conformation with internal motion described by fluctuations of 5–10° in glycosidic dihedral angles consistent with previous studies. Greater flexibility was observed for the remaining GlcNAc1→3‐β‐D ‐Gal and β‐D ‐Gal1→4Glc linkages, with the former glycosidic linkage existing in a conformational exchange among three states. The results were also supported by similar results of calculations carried out with conformers obtained from a simple Monte Carlo simulation without explicit solvent. © 2010 Wiley Periodicals, Inc. Biopolymers 95: 39–50, 2011.     

Sulfated oligosaccharides isolated from the respiratory mucins of a secretor patient suffering from chronic bronchitis

The most acidic carbohydrate chains released by alkaline borohydride treatment of the bulk of airway mucins secreted by a patient (blood group O, secretor) suffering from a mildly infected chronic bronchitis have been fractionated using high-performance anion-exchange chromatography (HPAEC) according to a protocol already described [Lo-Guidice et al., J. Biol. Chem. 269 (1994) 18794] and were analyzed using 1H-NMR spectroscopy and matrix-assisted laser-adsorption-time-of-flight (MALDI-TOF) spectrometry. Many fractions corresponded to mixtures of oligosaccharides. This confirmed the wide diversity of the post-translational processes involved in the biosynthesis of airway mucins, which had already been observed in bronchial diseases, such as chronic bronchitis and cystic fibrosis (CF). Seven fractions were directly purified by HPAEC, allowing their structural determination. Six of them corresponded to 3-O-sulfated oligosaccharide chains terminated by a sulfated N-acetyllactosamine, a sulfated Lewis X or a sulfated Lewis A determinant, and the last one corresponded to a 6-O-sulfated chain terminated by a sulfated H-2 determinant. Three oligosaccharides had core type 2 and the other four had core type 4: IIIc2-9: Gal(beta1-3)[HSO(3)-3-Gal(beta1-4)GlcNAc(beta1-6)]GalNAc-ol, IIIc2-10: Gal(beta1-3)[Fuc(alpha1-2)Gal(beta1-4)[HSO(3)-6-]GlcNAc(beta1-6)]GalNAc-ol, IIIc2-4: Fuc(alpha1-2)Gal(beta1-3)[HSO(3)-3-Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)]GalNAc-ol, IIIc2-8: Fuc(alpha1-2)Gal(beta1-3)GlcNAc(beta1-3)[HSO(3)-3-Gal(beta1-4)GlcNAc(beta1-6)]GalNAc-ol, IIIc2-7: Fuc(alpha1-2)Gal(beta1-3)GlcNAc(beta1-3)[Gal(beta1-4)[HSO(3)-6-]GlcNAc(beta1-6)]GalNAc-ol, IIIc2-3: Fuc(alpha1-2)Gal(beta1-3)GlcNAc(beta1-3)[HSO(3)-3-Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)]GalNAc-ol, IIIc1-4: Fuc(alpha1-2)Gal(beta1-3)GlcNAc(beta1-3)[HSO(3) -3-Gal(beta1-3)[Fuc(alpha1-4)]GlcNAc(beta1-3)Gal(beta1-4)GlcNAc(beta1-6)]GalNAc-ol. Like previous data concerning the airway mucins from another patient (blood group O and non-secretor) suffering from chronic bronchitis [Lo-Guidice et al., Glycoconj. J. 14 (1997) 113], no disialylated oligosaccharide and no sialylated and sulfated oligosaccharide bearing sialyl Lewis X epitope could be isolated. This is in contrast with the data obtained with the airway mucins secreted by the patient severely infected by Pseudomonas aeruginosa and suffering from CF, suggesting that important differences occur in the biosynthesis of airway mucins secreted by patients suffering from different bronchial diseases with or without severe infection.