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PubMed1990

Characterization of novel sequences containing 3-O-sulfated glucosamine in glomerular basement membrane heparan sulfate and localization of sulfated disaccharides to a peripheral domain.

Fragmentation of the heparan sulfate chains from bovine glomerular basement membrane (GBM) by hydrazine/nitrous acid treatment followed by NaB3H4-reduction yielded a mixture of six sulfated disaccharides containing D-glucuronic (GlcUA) or L-iduronic acid (IdUA) and terminating in 2,5-anhydro[3H]mannitol (AnManH2), in addition to the nonsulfated component GlcUA beta 1----4AnManH2. Among these products two novel disaccharide units were identified as IdUA alpha 1----4AnManH2(3-SO4) and IdUA(2-SO4)alpha 1----4AnManH2(3-SO4); these accounted for 22% of the total sulfated species indicating that there are 2-3 residues of 3-O-sulfated glucosamine/heparan sulfate chain. The disulfated disaccharide was shown through its release by direct nitrous acid treatment to be situated in a GlcNSO3-IdUA(2-SO4)-GlcNSO3(3-SO4) sequence which is distinct from that in which 3-O-sulfated glucosamine is located in the antithrombin-binding region of heparins. Analyses of heparan sulfate from lens capsule, a nonvascular basement membrane, indicated the absence of sequences containing 3-O-sulfated glucosamine, although otherwise the sulfated disaccharides produced by hydrazine/nitrous acid/Na-B3H4 treatment (GlcUA beta 1----4AnManH2(6-SO4), IdUA alpha 1----4AnManH2(6-SO4), IdUA(2-SO4)alpha 1----4AnManH2 and IdUA(2-SO4)alpha 1----4AnManH2(6-SO4] were the same as from GBM. Examination of the GBM heparan sulfate domains after nitrous acid treatment indicated that the O- as well as N-sulfate groups are clustered in an iduronic acid-rich 10-disaccharide peripheral segment, while the internal region (approximately 20 disaccharides) is composed primarily of repeating GlcUA beta 1----4GlcNAc units. The localization of chain diversity to the outer region may facilitate interactions of the heparan sulfate with other macromolecular components.

Animals↗
PubMed2004

Furcatin hydrolase from Viburnum furcatum Blume is a novel disaccharide-specific acuminosidase in glycosyl hydrolase family 1.

Furcatin hydrolase (FH) is a unique disaccharide-specific acuminosidase, which hydrolyzes furcatin (p-allylphenyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside (acuminoside)) into p-allylphenol and the disaccharide acuminose. We have isolated a cDNA coding for FH from Viburnum furcatum leaves. The open reading frame in the cDNA encoded a 538-amino acid polypeptide including a putative chloroplast transit peptide. The deduced protein showed 64% identity with tea leaf beta-primeverosidase, which is another disaccharide glycosidase specific to beta-primeverosides (6-O-beta-D-xylopyranosyl-beta-D-glucopyranosides). The deduced FH also shared greater than 50% identity with various plant beta-glucosidases in glycosyl hydrolase family 1. The recombinant FH expressed in Escherichia coli exhibited the highest level of activity toward furcatin with a Km value of 2.2 mm and specifically hydrolyzed the beta-glycosidic bond between p-allylphenol and acuminose, confirming FH as a disaccharide glycosidase. The FH also hydrolyzed beta-primeverosides and beta-vicianoside (6-O-alpha-L-arabinopyranosyl-beta-D-glucopyranoside) but poorly hydrolyzed beta-gentiobiosides (6-O-beta-D-glucopyranosyl-beta-d-glucopyranosides), indicating high substrate specificity for the disaccharide glycone moiety. The FH exhibited activity toward p-allylphenyl beta-D-glucopyranoside containing the same aglycone as furcatin but little activity toward the other beta-D-glucopyranosides. Stereochemical analysis using 1H NMR spectroscopy revealed that FH is a retaining glycosidase. The subcellular localization of FH was analyzed using green fluorescent protein fused with the putative N-terminal signal peptide, indicating that FH is localized to the chloroplast. Phylogenetic analysis of plant beta-glucosidases revealed that FH clusters with beta-primeverosidase, and this suggests that the disaccharide glycosidases will form a new subfamily in glycosyl hydrolase family 1.

Amino Acid Sequence↗
PubMed1994

High-resolution separation of disaccharide and oligosaccharide alditols from chondroitin sulphate, dermatan sulphate and hyaluronan using CarboPac PA1 chromatography.

Recent literature indicates that specific glycosaminoglycan structures are involved in various biological processes, such as anticoagulation, growth factor activation and viral infection. The initial step in the structural analysis of glycosaminoglycans is a definitive compositional analysis of its characteristic disaccharide repeat structures. Current chromatographic or electrophoretic procedures may have limitations in analysing glycosaminoglycan samples that are in low abundance, contain novel structures that need to be further characterized, or are metabolically labelled from radioactive precursors as a result of biosynthetic experiments. This study presents a new methodology for analysing disaccharides and oligosaccharides derived from chondroitin sulphate, dermatan sulphate and hyaluronan that fulfils the above criteria. The procedure involves the separation of reduced forms of these glycoconjugates on a CarboPac PA1 column using alkaline eluants. This study adopted a strategy which uses specific enzymes to release these disaccharides from their glycosaminoglycan forms. A borohydride reduction reaction was modified to be compatible with the buffer conditions commonly used with these enzymes in order to quantitatively reduce the disaccharides to their alditol forms (thereby stabilizing them to alkaline pH). Chromatography conditions were established which separated all known disaccharide alditol structures from chondroitin sulphate, dermatan sulphate and hyaluronan with extremely high resolution in a single run. Integrated pulsed amperometry was compared to UV absorbance measurement at 232 nm as two sensitive methods for detecting these reduced disaccharides; most of them could be routinely detected in the range of 50-500 ng. Data are presented applying this method to quantify hyaluronan in a biological sample which contains approximately 5000 cells and only approximately 10 ng of hyaluronan. Additional data are presented to demonstrate that this procedure will also separate oligosaccharide alditols derived from hyaluronan.

Borohydrides↗
PubMed2005

Kinetic characterization of glycosidase activity from disaccharide conjugate to monosaccharide conjugate in Caco-2 cells.

Glycosidase activity influences the intestinal absorption of glycosides. Our previous study in rats suggested that disaccharide conjugates might be prototypes for pre-prodrugs aiming at the Na(+)/glucose co-transporter-mediated transport of prodrugs (drug glucoside) as a novel absorption pathway. One of the crucial factors is the formation of a glucoside drug from the disaccharide conjugate. Since there is a large species difference in metabolism, it is necessary to examine the cells and/or enzymes derived from human tissue to confirm this concept. In this paper, we kinetically characterized the glycosidase activity of disaccharide conjugates in Caco-2 cells. Disaccharide conjugates of p-nitrophenol (p-NP) (p-NP beta-cellobioside, p-NP beta-lactoside and p-NP beta-maltoside) were hydrolysed to p-NP beta-glucoside. beta-glucosidase or beta-galactosidase (lactase/phloridzin hydrolase, LPH) and alpha-glucosidase (sucrase-isomaltase) had different pH-dependent activities for disaccharide conjugates. At neutral pH, LPH has low affinity and low capacity, and sucrase-isomaltase has high affinity and high capacity, whereas at acid pH, LPH has high affinity and low capacity, and sucrase-isomaltase has low affinity and high capacity. The hydrolysis clearance calculated with Vmax/Km indicated that sucrase-isomaltase activity is much higher than LPH activity at either neutral or acid pH in Caco-2 cells. Since the hydrolysis rate of the disaccharide conjugate was highly dependent on the pH value and type of glycoside linkage, the appropriate selection of a glycoside form after consideration of these differences is the key to designing a sugar-conjugate prodrug.

Caco-2 Cells↗
PubMed1999

Use of breath hydrogen testing to detect experimentally induced disaccharide malabsorption in healthy adult dogs.

OBJECTIVE: To develop a noninvasive method to detect disaccharide malabsorption in dogs by measuring hydrogen concentration ([H2]) in exhaled breath before and after experimentally induced disaccharide malabsorption. ANIMALS: 8 healthy mixed-breed dogs. PROCEDURE: [H2] was measured every 30 minutes for 8 hours after administration of disaccharide solutions (lactose, 0.5 g/kg of body weight; lactose, 1.0 g/kg; sucrose, 2.0 g/kg; maltose, 1.5 g/kg; and lactose [0.5 g/kg] and sucrose [2.0 g/kg]) to determine reference ranges of [H2] for each solution, which were compared with [H2] in dogs with experimentally induced disaccharide malabsorption. To induce disaccharide malabsorption, dogs were given a mild overdose of lactose (1.5 g/kg) or a disaccharidase inhibitor. In the latter experiment, acarbose (10 mg/kg, PO) was given with the combination of lactose (0.5 g/kg) and sucrose (2 g/kg), and with maltose (1.5 g/kg). RESULTS: Overdosing with lactose resulted in [H2] persistently outside the reference range for lactose in 5 of 8 dogs. Acarbose administration resulted in [H2] persistently outside the reference range in 7 of 8 dogs that received a combination of sucrose and lactose but did not consistently affect [H2] after administration of maltose. CONCLUSIONS: Disaccharide malabsorption resulted in [H2] outside the reference ranges in most of the adult dogs studied, suggesting that the technique may be useful in detecting naturally occurring disaccharidase deficiency.

Acarbose↗
PubMed2002

Determination of twelve heparin- and heparan sulfate-derived disaccharides as 2-aminoacridone derivatives by capillary zone electrophoresis using ultraviolet and laser-induced fluorescence detection.

In quest for high sensitivities, we developed an ultrahigh capillary electrophoresis (CE) method for the structural analysis of heparin and heparan sulfate (HS) in biologic samples. Heparin and HS were digested with an equi-unit mixture of heparin lyases I, II and III and the obtained Delta-disaccharides were derivatized with the fluorophore 2-aminoacridone. All known twelve non-, mono-, di- and trisulfated Delta-disaccharides were completely resolved in a single run, using 50 mM phosphate buffer, pH 3.5, and reversed polarity at 30 kV. Relative standard deviation in migration times and peak areas as well as day-to-day variance ranged from 0.9 to 2.4%, suggesting a reproducible and precise method. Detection of 2-aminoacridone (AMAC)-derivatives of Delta-disaccharides by UV at 255 nm showed 2.8 and 10 times higher sensitivity than that of derivatized and non-derivatized ones at 232 nm. Laser-induced fluorescence detection with an Ar-ion laser source showed an approximately 100 times higher sensitivity than that obtained at 232 nm of the non-derivatized species. Application of this method to quantitative analysis of Delta-disaccharides derived from porcine intestinal mucosa heparin and bovine kidney HS showed excellent agreement with previously published methods, suggesting an accurate method. The developed method can be easily applied for the disaccharide analysis of heparin/HS at the attomole level with high accuracy, for distinguishing between heparin and HS and may be of value for studying their interactions with matrix effective molecules.

Aminoacridines↗
PubMed2004

Synthesis and conformational analysis of novel N(OCH3)-linked disaccharide analogues.

N(OMe)-linked disaccharide analogues, isosteric to the corresponding natural disaccharides, have been synthesized by chemoselective assembly of unprotected natural monosaccharides with methyl 6-deoxy-6-methoxyamino-alpha-D-glucopyranoside in an aqueous environment. The coupling reactions were found to be chemo- and stereoselective affording beta-(1-->6) disaccharide mimics when using Glc and GlcNAc; in the case of Gal, the beta-anomer was prevalent (beta:alpha=7:1). An iterative method for the synthesis of linear N(OMe) oligosaccharide analogues was demonstrated, based on the use of an unprotected monosaccharide building block in which an oxime functionality at C-6 is converted during the synthesis into the corresponding methoxyamino group. The conformational analysis of these compounds was carried out by using NMR spectroscopy, ab initio, molecular mechanics, and molecular dynamics methods. Optimized geometries and energies of fourteen conformers for each compound have been calculated at the B3LYP/6-31G* level. Predicted conformational equilibria were compared with the results based on NMR experiments and good agreement was found. It appears that N(OMe)-linked disaccharide analogues exhibit a slightly different conformational behavior to their parent natural disaccharides.

Carbohydrate Conformation↗
PubMed2003

Separation of capsular polysaccharide K4 and defructosylated K4 derived disaccharides by high-performance capillary electrophoresis and high-performance liquid chromatography.

A rapid, highly sensitive and reproducible high-performance capillary electrophoresis (HPCE) method (electrokinetic chromatography with sodium dodecyl sulfate) is described for the determination of disaccharides present in the polysaccharide from the uropathogenic Escherichia coli K4 bacteria (05:K4:H4) and its defructosylated product. Following chondroitinase digestion of K4 and its derivative, the two disaccharides, DeltaHexAFrc-GalNAc for K4 and deltaHexA-GalNAc for defructosylated K4, are separated and readily determined within 20 min on an uncoated fused-silica capillary using normal polarity at 20 kV and detection at 230 nm. Comparison was made by separation of these two disaccharides in isocratic strong-anion exchange HPLC. A linear relationship was found for the two unsaturated disaccharides over a wide range of concentrations, from approximately 0.5 to 5 micro g for high-performance liquid chromatography (HPLC) and from approximately 0.06 to 0.3 micro g for HPCE. The HPCE separation produced a greater detection sensitivity (about 10 times greater) than HPLC. The described methods were used to evaluate the defructosylation process of K4 under drastic acid conditions. Good correspondence was found for the amount of unsaturated disaccharides for the two techniques.

Bacterial Capsules↗
PubMed2004

Polyacrylamide gel electrophoresis of fluorophore-labeled hyaluronan and chondroitin sulfate disaccharides: application to the analysis in cells and tissues.

This report describes a new formulation of polyacrylamide gel electrophoresis of fluorophore-labeled saccharides (PAGEFS) for the analysis of hyaluronan (HA) and chondroitin sulfate (CS) Delta-disaccharides. PAGEFS relies on derivatization of reducing ends of HA- and the variously sulfated CS-derived Delta-disaccharides with 2-aminoacridone (AMAC), followed by electrophoresis under optimized buffer conditions (Tris-borate and Tris-HCl) and on polyacrylamide gels (25% T/3.75% C). The method was applied to the analysis of glycosaminoglycans (GAGs) from the human umbilical cord tissue and GAGs isolated from human aortic smooth muscle cell cultures. The obtained results were in agreement with those obtained after an analysis with high-performance liquid chromatography (HPLC). On the basis of these results, PAGEFS is a rapid and sensitive method for the analysis of the total amount of HA- and CS-derived disaccharides, as it allows analyzing 20 samples in minigels in one run and provides quantitation with relatively high sensitivity (less than 25 pmol per disaccharide). In addition, PAGEFS overcomes the lack of commercial gels described previously for the separation of AMAC-labeled disaccharides. Therefore, the method proposed here is an economic and useful tool for a fast screening of GAGs in biological samples, particularly when a high number of samples should be analyzed.

Aorta↗
PubMed2002

Determination of the chondroitin sulfate disaccharides in dog and horse plasma by HPLC using chondroitinase digestion, precolumn derivatization, and fluorescence detection.

A sensitive and selective HPLC method for the determination of the disaccharides of chondroitin sulfate in horse and dog plasma was validated. Chondroitin sulfate is degraded by chondroitinase ABC to three primary unsaturated disaccharides, (1) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-D-galactose, (2) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose, and (3) 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose, when treated with chondroitinase. Plasma samples (0.5 ml) were treated with 50 mU of chondroitinase ABC in 50 microl of 1 mM sodium phosphate buffer (pH 7.0) at 37 degrees C for 6 h. The samples were extracted with 25% trifluoroacetic acid in ethanol. The resultant samples were derivatized with 1% dansylhydrazine in ethanol at 40 degrees C for 3 h. The chromatographic conditions consisted of fluorescence detection (excitation at 350 nm and emission at 530 nm), mu-Bondapack NH(2) (300 x 3.9 mm), and mobile phase of acetonitrile:100 mM acetate buffer, pH 5.6 (76:24), pumped at 1.0 ml/min. The standard curves for each chondroitin disaccharide showed linearity over the selected concentration range (r > or = 0.99). The intraday percentage relative standard deviation was < or =9.5% and the interday precision was < or =6.9% or less. The relative intraday and interday error ranged from -7.3 to 6.6% for each chondroitin disaccharide in the plasma. The extraction recovery was found to be in the range of 90-96%. The validated method accurately quantitated the disaccharides of chondroitin sulfate after administration to dogs and horses.

Animals↗
PubMed1999

Crystal structure of chondroitinase B from Flavobacterium heparinum and its complex with a disaccharide product at 1.7 A resolution.

Glycosaminoglycans (GAGs) are a family of acidic heteropolysaccharides, including such molecules as chondroitin sulfate, dermatan sulfate, heparin and keratan sulfate. Cleavage of the O-glycosidic bond within GAGs can be accomplished by hydrolases as well as lyases, yielding disaccharide and oligosaccharide products. We have determined the crystal structure of chondroitinase B, a glycosaminoglycan lyase from Flavobacterium heparinum, as well as its complex with a dermatan sulfate disaccharide product, both at 1.7 A resolution. Chondroitinase B adopts the right-handed parallel beta-helix fold, found originally in pectate lyase and subsequently in several polysaccharide lyases and hydrolases. Sequence homology between chondroitinase B and a mannuronate lyase from Pseudomonas sp. suggests this protein also adopts the beta-helix fold. Binding of the disaccharide product occurs within a positively charged cleft formed by loops extending from the surface of the beta-helix. Amino acid residues responsible for recognition of the disaccharide, as well as potential catalytic residues, have been identified. Two arginine residues, Arg318 and Arg364, are found to interact with the sulfate group attached to O-4 of N-acetylgalactosamine. Cleavage of dermatan sulfate likely occurs at the reducing end of the disaccharide, with Glu333 possibly acting as the general base.

Amino Acid Sequence↗
PubMed1999

Cytochemical localization of GalNAc and GalNAcbeta1,4Galbeta1,4 disaccharide in mouse zona pellucida.

Carbohydrate residues contained in the zona pellucida play a key role in the process of sperm-egg interaction. In vitro fertilization experiments have shown that a specific monoclonal antibody against GalNAcbeta1,4Galbeta1,4 disaccharide inhibits fertilization in mice. In the present study, the ultrastructural cytochemical localization of GalNAc residues and the GalNAcbeta1,4Galbeta1,4 disaccharide was carried out in ovarian and postovulatory oocytes by using lectin-gold cytochemistry and immunocytochemistry. Plant lectins SBA and DBA showed an affinity for the entire zona pellucida matrix of ovarian oocytes throughout the follicular maturation; however, immunoreactivity for GalNAcbeta1,4Galbeta1,4 disaccharide was not detected in ovarian oocytes at the earliest stages of follicular development but was found to be associated with the inner region of the zona matrix at the trilaminar primary follicle stage. The Golgi apparatus, vesicular aggregates, and cortical granules of the oocyte were intensely labeled by SBA and DBA throughout follicular development. Immunoreactivity to GalNAcbeta1,4Galbeta1,4 disaccharide was first observed in the Golgi apparatus and vesicular aggregates in trilaminar primary follicles. No immunoreactivity was observed in the cortical granules. In postovulatory oocytes, results were similar to those observed in ovarian oocytes. Our results thus suggest that (1) GalNAcbeta1,4Galbeta1,4 disaccharide residues are present only in the inner region of the zona pellucida and, therefore, might be involved in sperm penetration through the zona pellucida, (2) the inner and outer regions of the zona pellucida contain different oligosaccharide chains, (3) the vesicular aggregates detected in the oocyte could represent an intermediate step in the secretory pathway of zona pellucida glycoproteins and might be involved in the formation of cortical granules.

Animals↗
PubMed1985

Enzymatic analysis with chondrosulfatases of constituent disaccharides of sulfated chondroitin sulfate and dermatan sulfate isomers by high-performance liquid chromatography.

Various under-sulfated, monosulfated, and over-sulfated chondroitin sulfate and dermatan sulfate isomers were analyzed in terms of disaccharide units before or after desulfation with chondrosulfatases in addition to digestion with chondroitinases. The unsaturated disaccharides were separable by a high-performance liquid chromatography (HPLC) method using a resin made from a sulfonized styrene-divinylbenzene copolymer. The retention times of the parent sulfated unsaturated disaccharides and newly generated unsaturated mono- or nonsulfated disaccharides were reproducible. On desulfation of the parent sulfated unsaturated disaccharides with chondrosulfatases, almost all delta Di-S showed the same retention times as those of standard delta Di-S from known components. Following digestion of delta Di-diSB with chondro-4-sulfatase as well as delta Di-diSD or delta Di-diSG with chondro-6-sulfatase, three delta Di-monoS with the same retention time were detected with the HPLC method. These newly generated delta Di-monoS2 showed that the structure is N-acetyl-D-galactosamine, uronic acid 2-sulfate.

Chondroitin↗
PubMed1985

A high-performance liquid chromatography for constituent disaccharides of chondroitin sulfate and dermatan sulfate isomers.

An improved high-performance liquid chromatography for unsaturated disaccharides prepared from chondroitin sulfate and dermatan sulfate isomers was developed using an ion-exchange resin made from a sulfonized styrene-divinylbenzene copolymer. By this newly devised method, it was found that the retention times of representative unsaturated disaccharides are very unique and appear in the following order: unsaturated 6-sulfated, nonsulfated, and 4-sulfated disaccharides. The content of the individual unsaturated disaccharides could be measured at similar sensitivities with ultraviolet absorbance. Sensitive and unique retention times as well as good resolution were found for various unsaturated disulfated disaccharides. The new microassay method by HPLC can be used to determine chondroitin sulfate and dermatan sulfate isomers in amounts as small as 100 ng to 8 micrograms. The practicality of this method was verified by application to the separation and quantitation of chondroitin sulfate and dermatan sulfate isomers from human coronary arteries.

Adult↗
PubMed1989

Analysis of unsaturated disaccharides from glycosaminoglycuronan by high-performance liquid chromatography.

A rapid and simple analytical method for unsaturated disaccharide isomers formed by enzymatic digestion from hyaluronic acid, chondroitin sulfate, dermatan sulfate, heparan sulfate, and heparin by high-performance liquid chromatography using an amine-bound silica column with a linear gradient of sodium dihydrogen phosphate was developed. The analyses were performed on isomers of two groups belonging to the chondroitin sulfate family and the heparin sulfate family. In both families, disaccharide isomers eluted in the order non-, mono-, di-, and trisulfated disaccharides by elevating salt concentrations. The method was applied to the analysis of constituent disaccharides of representative sulfated glycosaminoglycans, which proved that most constituents could be quantified separately. This method is advantageous in that enzymatic digests can be applied directly on a column without any pretreatment and good resolution of several disaccharides can be obtained by one chromatography.

Chondroitin↗
PubMed1989

Synthesis of galactofuranose disaccharides of biological significance.

Methyl beta-D-galactofuranoside was readily obtained by tin(IV) chloride-catalyzed glycosylation of penta-O-benzoyl-alpha,beta-D-galactofuranose, followed by debenzoylation with sodium methoxide. Glycosylation of 1 with 2,3,5-tri-O-benzoyl-D-galactono-1,4-lactone or with the 6-O-trityl-lactone derivative 5 gave the benzoylated beta-D-galactofuranosyl-(1----6)-D-galactono-1,4-lactone 6 in excellent yield. The structure of disaccharide 6 was confirmed by borohydride reduction to the glycosyl-alditol 7. A byproduct of the condensation reaction of 1 with 4 or 5 was identified as the benzoylated (1----1)-beta,beta'-D-galactofuranosyl disaccharide 8. Compound 8 was readily prepared (88% yield) by controlled addition of water to 1, in the presence of stannic chloride. O-Debenzoylation of 8 afforded crystalline beta'-D-galactofuranosyl-(1----1)-beta-D-galactofuranoside. The glycosyl-lactone 6 constitutes a key intermediate for the synthesis of a disaccharide derivative having both units in the furanoid form. Thus, diisoamylborane reduction of the lactone function of 6 led to the disaccharide derivative 10, from which the methyl glycoside 12 was prepared. O-Debenzoylation of 12 gave the corresponding methyl beta-D-galactofuranosyl-(1----6)-beta-D-galactofuranoside. The free disaccharide beta-D-Galf-(1----6)-D-Galp and its acetylated derivative were also synthesized from 10.

Carbohydrate Conformation↗
PubMed1993

Structure of heparan sulfate from the fresh water mollusc Anomantidae sp: sequencing of its disaccharide units.

1. The disaccharide sequences of a heparan sulfate isolated from Anomantidae sp. was determined with the aid of heparitinase I, heparitinase II from Flavobacterium heparinum, mollusc beta-glucuronidase and alpha-N-acetylglucosaminidase besides nitrous acid degradation and chemical analyses. 2. Like the mammalian heparan sulfates the mollusc heparan sulfate is composed of different oligosaccharide blocks of N-acetylated disaccharides, N-sulfated disaccharides and N,6-sulfated disaccharides and has in its nonreducing end the monosaccharide glucosamine 2,6-disulfate. 3. The oligosaccharides produced by heparitinase I degradation contain at their reducing ends a N-acetylated, 6-sulfated disaccharide. 4. These and other results lead to the conclusion that the general structure of the heparan sulfate is maintained through evolution.

Acetylation↗
PubMed1995

Determination of hyaluronan and galactosaminoglycan disaccharides by high-performance capillary electrophoresis at the attomole level. Applications to analyses of tissue and cell culture proteoglycans.

A rapid, highly sensitive and reproducible HPCE method is described for the determination of all non- and variously sulphated disaccharides present in hyaluronan and vertebrate chondroitin sulphates and dermatan sulphates. Following chondroitinase digestion of glycosaminoglycans or proteoglycans, the non-, di- and tri-sulphated delta-disaccharides are completely separated and readily determined within 14 min on a fused-silica capillary in 15 mM sodium dihydrogen orthophosphate, pH 3.00, using reversed polarity at 20 kV and detection at 232 nm. The determination of the various delta-disaccharides derived from either glucuronic or iduronic acid and the presence of glucuronic and iduronic clustered structures in dermatan sulphate can also easily be made, using digests with chondroitinase AC or B. A linear detector response was obtained for the entire interval tested (up to 10 mg/l of delta-disaccharides). Concentrations as small as 32, 65, 100 and 250 pmol/l (22, 38, 50 and 98 ng/l) of tri-, di- and nonsulphated delta-disaccharides, respectively, can be reliably detected.

Animals↗