Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Disaccharides”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,459 records · Page 81Linked to original sources
PubMed1981

The chemical structure of the lipid A component of lipopolysaccharides from Vibrio cholerae.

The chemical structure of the lipid A component of the lipopolysaccharide from Vibrio cholerae 95R was studied. After sequential degradation a reduced D-glucosamine disaccharide was isolated from lipid A and, after permethylation, shown by combined gas-liquid chromatography/mass spectrometry to be beta 1,6-linked. The disaccharide is substituted with a phosphate group, ester-bound to the non-reducing glucosamine (GlcN) residue and a pyrophosphorylethanolamine group (PP-Etn) linked to C-1 of the reducing glucosamine residue. This backbone structure is shown in the following formula: P-GlcN(beta 1-6)GlcN-1-PP-Etn. The amino groups of the glucosamine disaccharide are substituted by D-3-hydroxytetradecanoic acid; tetradecanoic, hexadecanoic and a D-3-O-(D-3-hydroxydodecanoyl)-dodecanoic acid residue are linked to hydroxyl groups. A similar fatty acid composition was detected in lipopolysaccharides from Inaba, Ogawa and NAG strains of V. cholerae.

Chromatography, Gas↗
PubMed1996

Structural analysis of unsaturated hexasaccharides isolated from shark cartilage chondroitin sulfate D that are substrates for the exolytic action of chondroitin ABC lyase.

The enzymatic action of highly purified chondroitin ABC lyase from Proteus vulgaris is dependent on the size of the substrate, and the enzyme does not cleave tetrasaccharides, irrespective of their sulfation profiles [Sugahara, K., Shigeno, K., Masuda, M., Fujii, N., Kurosaka, A. & Takeda, K. (1994) Carbohydr. Res. 255, 145-163]. To characterize the enzyme action in more detail, we isolated nine sulfated hexasaccharides from commercial shark cartilage chondroitin sulfate D, after partial digestion with highly purified chondroitin ABC lyase, by means of gel chromatography and HPLC on an amine-bound silica column. Structural analysis by 500-MHz H-NMR spectroscopy, and enzymatic digestion in conjunction with HPLC, demonstrated that these hexasaccharides, with the common core saccharide structure delta 4 HexA (alpha 1-3)GalNAc(beta 1-4)GlcA(beta 1-3)GalNAc(beta 1-4) GlcA(beta 1-3)GalNAc(where delta 4 HexA and GlcA represent 4-deoxy-alpha-L-threo-hex-4-enepyranosyluronic acid and glucuronic acid, respectively) bear three or four sulfate groups in different combinations. In the hexasaccharides, the D, disaccharide unit GlcA2-SO3 (beta 1-3) GalNAc4SO(3-) which is characteristic of chondroitin sulfate D, was arranged on the reducing side of the A disaccharide unit GlcA(beta 1-3)GalNAc4SO(3)-, and thus formed an A-D tetrasaccharide sequence GlcA(beta 1-3)GalNAc4SO(3)-(beta 1-4)GlcA2SO(3)-(beta 1-3) GalNAc6SO(3)-. Analysis of the degradation products of these hexasaccharides with highly purified chondroitin ABC lyase indicated that the enzyme preferentially acted on the unsaturated hexasaccharides in an exolytic fashion and removed an unsaturated disaccharide unit from the non-reducing termini, irrespective of the sulfation profiles of the hexasaccharides.

Animals↗
PubMed1997

Biosynthesis of the proteoglycan decorin -- identification of intermediates in galactosaminoglycan assembly.

Biosynthesis of decorin was investigated by incubating a rat fibroblast cell line with various radiolabelled protein and galactosaminoglycan precursors. The following cell-associated and distinct intermediates were isolated and identified: a pool of non-glycosylated core protein, two pools of decorin with incomplete chains, one with three sulphated disaccharide repeats and another with five or more sulphated disaccharide repeats, as well as decorin with mature chains. Results of pulse/chase experiments indicated that these pools represented discrete stages in chain growth. Treatment with brefeldin A, which blocks transport from the endoplasmic reticulum to the Golgi, resulted in accumulation of decorin with an incomplete chain containing six or seven largely unsulphated disaccharide repeats. During recovery from drug treatment, 4-sulfation reappeared earlier than 6-sulfation. The results suggest that the galactosaminoglycan assembly-line consists of separate multienzyme complexes that build only a limited section of the chain. Furthermore, brefeldin A causes segregation of compartments involved in separate stages of the assembly line. In an earlier report [Moses, J., Oldberg. A., Cheng, F. & Fransson, L.-A. (1997) Eur. J. Biochem. 248, 521-526] we took advantage of such segregation to identify and characterize a transient 2-phosphorylation of xylose in the linkage region.

Amino Acid Sequence↗
PubMed1996

High-performance liquid chromatography analysis of chondroitin sulphate isomers in human whole saliva in a variety of clinical conditions.

OBJECTIVES: Tests have been carried out to assess the level of unsaturated disaccharide isomers obtained from chondroitin sulphate in whole saliva, which contains chondroitin sulphate derived from gingival crevicular fluid (GCF). MATERIALS AND METHODS: Whole saliva was collected from periodontally diseased subjects (PDS), clinically healthy subjects (CHS) and edentulous subjects (ES). Glycosaminoglycans (GAG) were liberated by digestion with Pronase E, and precipitated with cetylpyridinium chloride and ethanol. The unsaturated disaccharides obtained by chondroitinase ACII digestion of the liberated GAG were analysed by high-performance liquid chromatography. The unsaturated disaccharides included delta Di-0S, delta Di-6S and delta Di-4S. RESULTS AND CONCLUSIONS: Analysis of data indicated that delta Di-0S, delta Di-6S and delta Di-4S were found in all PDS samples. The amount (ng ml-1 collected whole saliva) of delta Di-0S, delta Di-6S and delta Di-4S (P < 0.01) indicated significant differences between CHS and PDS whole saliva samples. The quantities of delta Di-0S and delta Di-4S (P < 0.01) indicated significant differences between PDS and ES whole saliva. The amount of delta Di-0S (P < .05) and delta Di-6S (P < 0.01) also indicated significant differences between CHS and ES whole saliva. These results indicate that chondroitin sulphate in PDS and CHS whole saliva is representative of that previously reported in gingival crevicular fluid and so provides a useful and alternative means of assessing the role of GAG as indicators of periodontal disease.

Adult↗
PubMed1976

Glycosaminoglycans of cartilage and bone tissue in two cases of osteogenesis imperfecta congenita.

Epiphyseal cartilage and bone tissue from two cases of osteogenesis imperfecta congenita and one control case with similar skeletal age were examined regarding their glycosaminoglycan content. The diseased bone tissue showed a 3-fold increase in glycosaminoglycans, and 20-25 per cent of the chondroitin sulphate disaccharides seemed to be disulphated. The diseased cartilages showed only traces of material with characteristics of disulphates disaccharides. No disulphates disaccharides were isolated from the control materials. No difference between diseased and control material was indicated regarding molecular size, chondroitin-4-sulphate/chondroitin-6-sulphate ratio or contents of keratan sulphate and hyaluronic acid. The disease is thus associated with fundamental changes of the glycosaminoglycan structure, and these changes may be of functional importance to the mineralization process as well as to the organisation of collagen.

Bone and Bones↗
PubMed1987

Alterations in peptidoglycan of Neisseria gonorrhoeae induced by sub-MICs of beta-lactam antibiotics.

Exposure of Neisseria gonorrhoeae to sub-MICs of selected beta-lactam antibiotics caused distortion of normal cell morphology. Analysis of the peptidoglycan indicated that the cells were accumulating increased quantities of disaccharide pentapeptide in their cell walls. The O-acetylated form of the disaccharide pentapeptide was not detected among the major peaks. The correlation of antibiotic binding to gonococcal penicillin-binding protein 2 and accumulation of non-O-acetylated disaccharide pentapeptide suggested an explanation for the previously observed relationship of penicillin-binding protein 2 and O-acetylation of peptidoglycan.

Acyltransferases↗
PubMed1987

The immunogenicity and antigenicity of lipid A are influenced by its physicochemical state and environment.

We investigated the immunogenicity and antigenicity of synthetic lipid A and partial structures thereof. Included in the study were compounds which varied in the position of phosphate (1-mono-, 4'-mono-, and 1,4'-bisphosphates) and in the acylation (type, number, and distribution of fatty acids) and, in the case of monosaccharide compounds, the nature of the backbone sugar (D-glucosamine, D-glucose, 3-amino-3-deoxy-D-glucose, and 2,3-diamino-2,3-dideoxy-D-glucose). With the aid of the passive-hemolysis and passive-hemolysis-inhibition assays and by absorption experiments, five distinct antibody specificities were detected in polyclonal rabbit antisera raised against sheep erythrocyte-coated lipid A and lipid A incorporated into the membrane of liposomes (liposome-incorporated immunogens). Three antibody specificities reacted with disaccharide antigens specific for a 1-mono-, 4'-mono-, and 1,4'-bisphosphorylated beta-1,6-linked D-glucosamine disaccharide. Two antibodies reacted with either 1- or 4-phosphates of acylated D-gluco-configured monosaccharides and exhibited no cross-reaction with each other. However, they cross-reacted with disaccharide antigens with phosphate groups in the appropriate positions. We found that the physicochemical state and the environment of lipid A modulated its immunoreactivity. The immunogenicity was best expressed by erythrocyte-coated and liposome-incorporated immunogens. The antigenicity of lipid A was also greatly influenced by its physical surroundings. The reaction pattern of the above antibodies was highly specific in the hemolysis assay and in absorption experiments (the antibody reacted with antigen embedded in a cell membrane), whereas some cross-reactivities were observed in inhibition studies (the antibody reacts with antigen in aqueous solution). By using liposome-incorporated antigens as inhibitors, nonspecific reactions were avoided and specific ones were enhanced. Thus the antibodies described above against lipid A recognize epitopes in the hydrophilic backbone, the exposure of which depends on the intrinsic physicochemical properties of lipid A on the one hand and the physical environment on the other.

Animals↗
PubMed1996

The major fimbrial subunit of Bordetella pertussis binds to sulfated sugars.

Bordetella pertussis fimbriae are composed of major and minor subunits, and recently it was shown that the minor fimbrial subunit binds to Vla-5, a receptor located on monocytes (W. Hazenbos, C. Geuijen, B. van den Berg, F. Mooi, and R. van Furth, J. Infect. Dis. 171:924-929, 1995). Here we present evidence that the major subunits bind to sulfated sugars, which are ubiquitous in the respiratory tract. Binding was observed to chondroitin sulfate, heparan sulfate, and dextran sulfate but not to dextran. Removal of the minor subunit from fimbriae did not significantly affect binding to sulfated sugars, indicating that the major subunit alone is sufficient for this binding. Fimbriae were also able to bind HEp-2 cells, which are known to display glycoconjugates on their surface. This binding was not dependent on the presence of the minor subunit. However, binding was dependent on the sulfation state of the glycoconjugates, since inhibition of the sulfation resulted in a significant reduction of fimbria binding. The specificity of fimbria binding was further characterized by using heparan sulfate-derived disaccharides in inhibition assays. Two disaccharides were highly effective inhibitors, and it was observed that both the degree of sulfation and the arrangement of the sulfate groups on the disaccharides were important for binding to fimbriae. B. pertussis bacteria also bound to sulfated sugars and HEp-2 cells, and analysis of B. pertussis mutants indicated that both filamentous hemagglutinin and fimbriae were required for this binding. A host protein present in the extracellular matrix, fibronectin, has binding activities similar to those of B. pertussis fimbriae, binding to both Vla-5 and sulfated sugars. Two regions in the major fimbrial subunit were identified which showed similarity with fibronectin peptides which bind to sulfated sugars. Thus, B. pertussis fimbriae exemplify molecular mimicry and may co-opt host processes by mimicking natural ligand-receptor interactions.

Amino Acid Sequence↗
PubMed1982

Peptidoglycan of Rhodopseudomonas viridis: partial lack of N-acetyl substitution of glucosamine.

A lack of at least 70% of N-acetyl substitution of glucosamine in the glycan strands of the peptidoglycan from the gram-negative bacterium Rhodopseudomonas viridis is reported. A disaccharide, very likely GlcN beta(1 leads to 4) Mur, was observed in hydrolysates of the isolated peptidoglycan. The disaccharide was not observed when peptidoglycan was N-acetylated before hydrolysis. The peptidoglycan of R. viridis was resistant to lysozyme but became sensitive after N-acetylation with acetic anhydride. The disaccharide was found with peptidoglycan from all R. viridis strains investigated, as well as with R. sulfoviridis P1 and R. palustris strains, but not with peptidoglycan from R. gelatinosa, Rhodospirillum tenue, and Pseudomonas diminuta NCTC 8545.

Acetylation↗
PubMed1985

Accumulation of alpha,alpha-trehalose by Rhizobium bacteria and bacteroids.

Four strains of Rhizobium japonicum (61A76 and USDA 110, 123, and 138) were grown in eight different defined media. Regardless of the carbon or nitrogen source supplied, alpha, alpha-trehalose was the major carbohydrate (among mono- and disaccharides) accumulated by all four strains. After 7 to 9 days of growth, trehalose generally accounted for 90 to 100% of the mono- and disaccharides detected. None of the four strains would grow with trehalose as a carbon source, but the utilization of endogenous trehalose was demonstrated under carbon starvation conditions in water culture or when the carbon supply in a defined medium was exhausted. Under these conditions, a small amount of trehalose was lost from cells to the medium. In a survey of most of the serogroups of R. japonicum and several strains of other Rhizobium species, all strains tested were found to accumulate some trehalose. Trehalose concentrations varied widely; the highest concentration recorded was 41 micrograms/mg of dry weight. In all but six strains trehalose accounted for greater than 80% of the mono- and disaccharides in cells. Fast-growing strains of R. japonicum also accumulated small amounts trehalose. R. japonicum bacteroids also synthesized trehalose; the quantity in nodules varied in approximate correspondence to accumulation of trehalose by cultured bacteria. In young soybean nodules (29 days after planting), 45 to 80% of the trehalose was recovered in the cytosol. There were differences among R. japonicum strains in the retention of trehalose, and the proportion of trehalose retained by bacteroids increased with increasing plant age for all strains.

Culture Media↗
PubMed1990

Polymer length of teichuronic acid released from cell walls of Micrococcus luteus.

Teichuronic acid released from its phosphodiester linkage to peptidoglycan in the cell walls of Micrococcus luteus by mild acid treatment is resolved into a ladderlike series of bands by electrophoresis on polyacrylamide gels in the presence of borate. Each band of the ladder differs from its nearest neighbor by one disaccharide repeat unit, ----4)-2-acetamido-2-deoxy-beta-D-mannopyranuronosyl-(1----6)- alpha-D-glucopyranosyl-(1-. Acid-fragmented teichuronic acid, after conversion to the phenylamine derivative, was fractionated by preparative-scale molecular sieve column chromatography, which produced a series of elution peaks. Fast-atom-bombardment mass spectrometry of the smallest member of the series determined its molecular weight and established its identity as the phenylamine derivative of one disaccharide repeat unit of teichuronic acid. Homologous fractions of the same series were used to index the ladder of bands obtained by polyacrylamide gel electrophoresis from samples containing a more extensive distribution of polymer lengths. Nearly native teichuronic acid consists of polymers with a broad range of molecular sizes ranging from 20 to 55 disaccharide units. The most abundant species are those which have 25 to 40 repeat units. Prolonged treatment of teichuronic acid with the acid conditions used to release it from peptidoglycan causes gradual fragmentation of the teichuronic acid.

Carbohydrate Sequence↗
PubMed1997

2-Sulfotrehalose, a novel osmolyte in haloalkaliphilic archaea.

A novel 1-->1 alpha-linked glucose disaccharide with sulfate at C-2 of one of the glucose moieties, 1-(2-O-sulfo-alpha-D-glucopyranosyl)-alpha-D-glycopyranose, was found to be the major organic solute accumulated by a Natronococcus sp. and several Natronobacterium species. The concentration of this novel disaccharide, termed sulfotrehalose, increased with increasing concentrations of external NaCl, behavior consistent with its identity as an osmolyte. A variety of noncharged disaccharides (trehalose, sucrose, cellobiose, and maltose) were added to the growth medium to see if they could suppress synthesis and accumulation of sulfotrehalose. Sucrose was the most effective in suppressing biosynthesis and accumulation of sulfotrehalose, with levels as low as 0.1 mM being able to significantly replace the novel charged osmolyte. Other common osmolytes (glycine betaine, glutamate, and proline) were not accumulated or used for osmotic balance in place of the sulfotrehalose by the halophilic archaeons.

Disaccharides↗
PubMed1999

Chondroitin sulphation patterns in synovial fluid in osteoarthritis subsets.

OBJECTIVES: To determine concentrations of chondroitin sulphate (CS) disaccharides in knee synovial fluid (SF) from normal subjects and patients with osteoarthritis (OA) or rheumatoid arthritis (RA), to test whether these variables differ between different diseases and subsets of OA. METHODS: OA was subdivided into large joint OA (LJOA), nodal generalised OA (NGOA), and OA with calcium pyrophosphate crystal deposition (CPA), with 25, 9, and 11 people in each subset respectively. The SF of 13 normal subjects was also volunteered for analysis along with 15 RA patients. Clinical assessment of inflammation (0-6) was undertaken on OA and RA knees. Concentrations of unsaturated CS disaccharides Deltadi6S and Deltadi4S were measured by capillary zone electrophoresis. RESULTS: Concentrations of Deltadi6S were lower in RA (5.90 ng/ml) and OA (13.24 ng/ml) fluids compared with normal (21.0 ng/ml) but no significant differences were seen between disease and normal fluids for Deltadi4S (about 4-6 ng/ml). The ratio of Deltadi6S:Deltadi4S were RA<OA<normal subjects (p<0.001 for all comparisons). The disaccharide concentration values along with the ratios are below. Higher Deltadi6S:Deltadi4S ratios were obtained for LJOA and CPA compared with NGOA. Uninflamed knees had lower concentrations of Deltadi6S than inflamed knees (p<0.01). In patients with bilateral samples, there were strong correlations between right and left knees for all SF variables. CONCLUSIONS: Altered ratios of CS sulphation patterns occur in OA and within OA subsets. These further justify considering NGOA as a subset with a different aetiopathogenesis.

Adult↗
PubMed1975

Occurrence and properties of fetal intestinal glycosidases (disaccharidases) in human amniotic fluid.

alpha-Glucosidase, beta-glucosidase and beta-galactosidase were studied in cell-free amniotic fluid samples using corresponding 4-methylumbelliferyl-glycosides and a series of disaccharides (maltose, sucrose, trehalose, turanose, cellobiose, gentiobiose and lactose) as substrates. The glycosidases exhibited several properties of intestinal disaccharidases such as pH optimum between 5.2 and 6.4, more activity towards the disaccharides than the artificial substrates, tight association of the activities with sedimentable complexes and beta-glucosidase and beta-galactosidase activities exerted by a single catalytic site. With the disaccharides as substrates, the amniotic fluid glycosidase activities were well correlated to those reported in the literature for fetal intestine of corresponding gestational ages. The presence of intestinal disaccharidases in amniotic fluid indicates that the fetal intestine contributes to the protein and enzymes of amniotic fluid.

Amniotic Fluid↗
PubMed1973

Brush border disaccharidases in dog kidney and their spatial relationship to glucose transport receptors.

The localization of disaccharidases in kidney has been studied by means of the multiple indicator dilution technique. A pulse injection of a solution containing Evans blue dye (plasma marker), creatinine (extracellular marker), and a (14)C-labeled disaccharide (lactose, sucrose, maltose, and alphaalpha-trehalose), is made into the renal artery of an anesthetized dog, and the outflow curves are monitored simultaneously from renal venous and urine effluents. Lactose and sucrose have an extracellular distribution. Trehalose and maltose remain extracellular from the postglomerular circulation. About 75% of filtered tracer maltose or trehalose is extracted by the luminal surface of the nephron. Thin-layer chromatography of urine samples shows that all of the excreted (14)C radiolabel is in the form of the injected disaccharide. Following the administration of phlorizin, all of the filtered radioactivity is recoverable in the urine, but chromatography of the urine samples now reveals that there is a significant excretion of [(14)C]glucose, approximating the amount previously extracted under control conditions (in the absence of phlorizin). It has been verified that no hydrolysis of maltose or trehalose to their constituent glucose subunits occurred during the transit of tracer between the point of injection (renal artery), and the point of filtration (glomerular basement membrane). Similarly, after addition of [(14)C]disaccharides to fresh urine there is no chromatographically recoverable [(14)C]glucose. It is concluded that there exist alpha-glucosidases with maltase and trehalase activity along the brush border of the proximal tubule and that these disaccharidases are located spatially superficial to the glucose transport receptors.

Animals↗
PubMed1993

Structural diversity of mammalian hepatic dermatan sulfates.

Dermatan sulfate-proteoglycans (DS-PGs) were extracted from rabbit, rat and bovine defatted livers by magnesium chloride extraction and DEAE-cellulose chromatography, and then submitted successively to Asahipak GS-520 gel filtration chromatography, Asahipak ES-502N anion exchange chromatography, and cellulose acetate membrane electrophoresis. The disaccharide composition of the glycosaminoglycan chains was determined by differential digestion by chondroitinase ABC, AC, ACII and/or B followed by HPLC for analysis of the resulting unsaturated disaccharides. The hepatic dermatan sulfate chains contained disulfated disaccharide units; Di-diSB and Di-diSE. The hepatic DS-PGs were divided into two groups; Di-diSE-poor DS-PGs and Di-diSE-rich DS-PGs. The iduronic acid content of Di-diSE-poor dermatan sulfate chains was higher than that of Di-diSE-rich ones.

Animals↗
PubMed1980

Chemical structure of urinary dermatan sulfate excreted by a patient with the Hunter syndrome.

The chemical structure of dermatan sulfate (DS) in the urine of a patient the Hunter syndrome was studied through the analysis of disaccharide units which were derived from the urinary DS by digestion with chondroitinase ABC and separated on a Dowex 1 column. The DS was basically composed of repeating disaccharide units of iduronyl N-acetylgalactosamine 4-sulfate. About 90% of the excess sulfate were linked to the iduronate residues as an additional sulfate group in the unit. N-Acetylgalactosamine 6-sulfate and N-acetylgalactosamine 4,6-disulfate residues were minor components. No non-sulfated disaccharide unit was detected in the digestion products. Only sulfoiduronate residue was found as the non-reducing terminal sugar of the DS molecule, consistent with the lack of iduronosulfate sulfatase in this disease.

Acetylgalactosamine↗
PubMedDate not supplied

Synthetic antigens as immunogens: Part IV. Specificity of antisera developed to Gal beta 1-3(GlcNAc beta 1-6)GalNAc and GlcNAc beta 1-6GalNAc.

Antisera to the chemically synthesized trisaccharide, Gal beta 1-3(GlcNAc beta 1-6)GalNAc, and disaccharide, GlcNAc beta 1-6GalNAc, were developed using the diazophenyl bovine serum albumin derivatives. The binding specificity of the antisera were analyzed by enzyme immunoassays with structurally related, chemically synthesized oligosaccharides. The anti-trisaccharide antibody showed no reactivity to T antigenic structures which bear the Gal beta 1-3GalNAc moiety. The immunodominant area of the Gal beta 1-3(GlcNAc beta 1-6)GalNAc was contained in the GlcNAc beta 1-6GalNAc region of the molecule. The reactivity pattern of the anti-trisaccharide antibody, although directed to the disaccharide, did not exactly duplicate the reactivity pattern of the anti-disaccharide.

Antibody Specificity↗