Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.6.4 (chondroitinase)
2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chondroitin 4-sulphate, chondroitin 6-sulphate, dermatan sulphate and keratan sulphate were N-deacetylated by treatment with hydrazine and then cleaved with HNO2 at pH 4.0, and the resulting products were reduced with NaB3H4. This reaction sequence cleaved the glycosaminoglycans at their N-acetyl-D-glucosamine or N-acetyl-D-galactosamine residues, which were converted into 3H-labelled 2,5-anhydro-D-mannitol (AManR) or 2,5-anhydro-D-talitol (ATalR) residues respectively. The end-labelled disaccharides, composed of D-glucuronic acid (GlcA), L-iduronic acid (IdoA) or D-galactose (Gal) and one of the anhydrohexitols, were identified as follows: both chondroitin 4-sulphate and chondroitin 6-sulphate gave GlcA----ATalR(4-SO4), GlcA----ATalR(6-SO4), IdoA----ATalR (4-SO4) and GlcA(2-SO4)----ATalR(6-SO4); dermatan sulphate gave IdoA----ATalR(4-SO4), GlcA----ATalR(4-SO4), GlcA----ATalR(6-SO4)----IdoA(2-SO4)ATalR(4-SO4) and IdoA----ATalR (4,6-diSO4); keratan sulphate gave Gal(6-SO4)----AManR(6-SO4), Gal----AManR(6-SO4), Gal(6-SO4)----AManR and Gal----AManR. Several additional disaccharides were generated by treatment of the uronic acid-containing disaccharides with hydrazine to epimerize their uronic acid residues at C-5. A number of these disaccharides were found to be substrates for lysosomal sulphatases and glycuronidases. Methods were developed for the separation of all of the disaccharide products by h.p.l.c. The rate of N-deacetylation of chondroitin 4-sulphate by hydrazinolysis was significantly lower than the rate of N-deacetylation of chondroitin 6-sulphate or chondroitin. Dermatan sulphate was N-deacetylated at an intermediate rate. The relative amounts of disaccharides obtained from chondroitin 4-sulphate, chondroitin 6-sulphate and dermatan sulphate under optimum hydrazinolysis/deamination conditions were comparable with the amounts of the corresponding products released from the polymers by chondroitinase treatment.
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PMID:The disaccharides formed by deaminative cleavage of N-deacetylated glycosaminoglycans. 374 82

A large Mr chondroitin sulfate proteoglycan was extracted from the media of human aorta under dissociative conditions and purified by density-gradient centrifugation, ion-exchange chromatography, and gel filtration chromatography. Removal of a contaminating dermatan sulfate proteoglycan was accomplished by reduction, alkylation and rechromatography on the gel filtration column. After chondroitinase ABC treatment, the proteoglycan core was separated from a residual heparan sulfate proteoglycan by a third gel filtration chromatography step. As assessed by radioimmunoassay, the isolated proteoglycan core was free of link protein, but possessed epitopes that were recognized by antisera against the hyaluronic acid binding region of bovine cartilage proteoglycan as well as those that were weakly recognized by anti-keratan sulfate antisera. Following beta-elimination of the protein core, the liberated low Mr oligosaccharides were partially resolved by Sephadex G-50 chromatography, and their primary structure was determined by 500-MHz1H NMR spectroscopy in combination with compositional sugar analysis. The N-glycosidic carbohydrate chains, which were obtained as glycopeptides, were all biantennary glycans containing NeuAc and Fuc; microheterogeneity in the NeuAc----Gal linkage was detected in one of the branches. The N-glycosidic glycans have the following overall structure: (Formula: see text). The majority of the O-glycosidic carbohydrate chains bound to the protein core were found to be of the mucin type. They were obtained as glycopeptides and oligosaccharide alditols, and possessed the following structures: NeuAc alpha(2----3)Gal beta(1----3)GalNAc-ol, [NeuAc alpha(2----3)Gal beta(1----3)[NeuAc alpha(2----6)]GalNAc-ol, and NeuAc alpha-(2----3) Gal beta(1----3)[NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)] GalNAc-ol. The remainder of the O-glycosidic carbohydrate chains bound to the isolated proteoglycan were the hexasaccharide link regions of the chondroitin sulfate chains that remained after chondroitinase ABC treatment of the native molecule. These latter glycans, which were obtained as oligosaccharide alditols, had the following structure (with GalNAc free of sulfate or containing sulfate bound at either C-4 or C-6): delta 4,5GlcUA beta(1----3)GalNAc beta(1----4)GlcUA beta(1----3)Gal beta(1----3)Gal beta(1----4)Xyl-ol.
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PMID:The structures of N- and O-glycosidic carbohydrate chains of a chondroitin sulfate proteoglycan isolated from the media of the human aorta. 381 52

A clone of natural killer (NK) cells (JTB18) was found to be ultrastructurally similar to peripheral blood large granular lymphocytes (LGL). These cells incorporated [35S]sulfate into cell-associated proteoglycan molecules, which were then isolated by CsCl density gradient centrifugation. As assessed by gel filtration chromatography, the native 35S-labeled proteoglycan and its beta-eliminated 35S-labeled glycosaminoglycans were of Mr approximately 200,000 and 50,000, respectively. The 35S-labeled proteoglycans were resistant to proteolysis, since their Mr were apparently not altered by incubation with either pronase or S. aureus V8 protease. The purified NK cell 35S-labeled proteoglycans were degraded by approximately 90% to 35S-labeled disaccharides with either chondroitinase ABC or AC. High performance liquid chromatographic analysis of the digests revealed these disaccharides to be composed entirely of chondroitin sulfate A (glucuronic acid----N-acetylgalactosamine-4SO4). Whole 35S-labeled cells incubated with chondroitinase ABC failed to release 35S-labeled disaccharides into the supernatant, and x-ray energy-dispersive analysis revealed that sulfur-containing molecules were present in the intracellular granules, thereby localizing the NK cell-associated proteoglycan primarily in the granules of the cell, rather than on the plasma membrane. The 35S-labeled cloned NK cells incubated for 30 min to 4 h with K562 tumor cell targets at a 0.5:1 ratio exocytosed a mean of 49% of the granular 35S-labeled proteoglycans during the first 60 min of the culture. Proteoglycan release was maximal with an effector/target cell ratio of 0.5:1 for JTB18:K562. Significant proteoglycan release from JTB18 NK cells was also obtained with other sensitive target cells such as REX, Molt4, and CEM, but not with cells such as KG1 and Laz156, which have been shown previously to be resistant to killing by this NK cell. Thus, protease-resistant intracellular proteoglycans with chondroitin sulfate A side chains are specifically exocytosed from the granules of human NK effector cells upon contact with sensitive targets, suggesting that these proteoglycans may be involved in the mechanism of cytotoxicity.
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PMID:Proteoglycans in cell-mediated cytotoxicity. Identification, localization, and exocytosis of a chondroitin sulfate proteoglycan from human cloned natural killer cells during target cell lysis. 393 16

A previous report from this laboratory (Kobayashi, S., Oguri, K., Kobayashi, K. and Okayama, M. (1983) J. Biol. Chem. 258, 12051-12057) indicated that isolated rat glomeruli synthesized three species of sulfated glycoconjugates in vitro, namely, sulfated glycoproteins, proteoheparan sulfates and proteochondroitin sulfates. In the present study, the proteochondroitin sulfates, which showed the greatest incorporation of [35S]sulfate among the three sulfated glycoconjugates, were isolated and characterized. Radiolabeled tissue proteochondroitin sulfates were clearly separated on Sepharose CL-6B into three components with partition coefficients (Kd) of 0.16, 0.22 and 0.58, and medium proteochondroitin sulfates were separated into two components with Kd values of 0.33 and 0.62. When the chondroitin sulfate chains released by alkaline borohydride treatment were analyzed by digestion with chondroitinase AC-II, chondroitinase ABC, chondro-6-sulfatase and chondro-4-sulfatase, the results showed that all the samples contained glucuronosyl-N-acetylgalactosamine (chondroitinase AC-II-susceptible sequences, 72-86%) and iduronosyl-N-acetylgalactosamine (chondroitinase ABC-susceptible sequences, 14-28%), containing 4-sulfated N-acetylgalactosamine (50-70%) and 4,6-disulfated N-acetylgalactosamine (30-50%). On two-dimensional electrophoresis on cellulose acetate, all samples gave a single spot which closely coincided with chondroitin sulfate E of squid cartilage in electrophoretic mobility. These results indicated that the chains were highly sulfated chondroitin sulfates containing glucuronic acid and iduronic acid residues.
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PMID:Highly sulfated proteochondroitin sulfates synthesized in vitro by rat glomeruli. 401 46

Dermatan sulphate was degraded by testicular hyaluronidase and an oversulphated fraction was isolated by ion-exchange chromatography. This preparation, which contained fairly long segments derived from the non-reducing terminal portion of the molecule, was subjected to periodate oxidation under acidic conditions. The oxidized iduronic acid residues were cleaved by reduction-hydrolysis (Smith-degradation) (Fransson & Carlstedt, 1974) or by alkaline elimination. The oligosaccharides so obtained contained both GlcUA (glucuronic acid) and IdUA-SO(4) (sulphated iduronic acid) residues. Copolymeric oligosaccharides obtained after alkaline elimination were cleaved by chondroitinase-AC into disaccharide and higher oligosaccharides. Since the corresponding oligosaccharides obtained by Smith-degradation were unaffected by this enzyme, it was concluded that the carbohydrate sequences were GalNAc-(IdUA-GalNAc)(n)-GlcUA-GalNAc. The iduronic acid-containing sequences were resistant to digestion with chondroitinase-ABC. It was demonstrated that the presence of unsulphated N-acetylgalactosamine residues in these sequences could be responsible for the observed effect. This information was obtained in an indirect way. Chemically desulphated dermatan sulphate was found to be a poor substrate for the chondroitinase-ABC enzyme. Moreover, digestion with chondroitinase-ABC of chondroitinase-AC-degraded dermatan sulphate released periodate-resistant iduronic acid-containing oligosaccharides. It is concluded that copolymeric sequences of the following structure are present in pig skin dermatan sulphate: [Formula: see text] N-acetylgalactosamine moieties surrounding IdUA-SO(4) residues are unsulphated to a large extent.
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PMID:The copolymeric structure of pig skin dermatan sulphate. Isolation and characterization of L-idurono-sulphate-containing oligosaccharides from copolymeric chains. 437 44

Selective periodate oxidation of unsubstituted l-iduronic acid residues in copolymeric dermatan sulphate chains was followed by reduction-hydrolysis or alkaline elimination. By this procedure the glucuronic acid-containing periods were isolated in oligosaccharide form; general formula: [Formula: see text] Further degradation of these oligosaccharides with chondroitinase-AC yielded three types of products: (a) sulphated trisaccharide containing an unsaturated uronosyl moiety in the non-reducing terminal and a C(4) fragment in the reducing terminal, DeltaUA-GalNAc-(-SO(4))-R; (b) monosulphated, unsaturated disaccharide, DeltaUA-GalNAc-SO(4) when n is greater than or equal to 2; and (c) N-acetylgalactosamine with or without sulphate. Oligosaccharides containing a single glucuronic acid residue (n=1) comprised more than half of the glucuronic acid-containing oligosaccharides. The terminal N-acetylgalactosamine moiety of the shortest oligosaccharide was largely 4-sulphated, whereas higher oligosaccharides primarily contained 6-sulphated or unsulphated hexosamine moieties in the same position. Moreover, IdUA-SO(4)-containing oligosaccharides were encountered. These oligosaccharides were resistant to the action of chondroitinase-ABC.
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PMID:The copolymeric structure of pig skin dermatan suplhate. Characterization of D-glucuronic acid-containing oligosaccharides isolated after controlled degradation of oxydermatan sulphate. 461 74

Bovine nasal cartilage proteoglycan monomer which had been digested with chondroitinase ABC to form the keratan sulfate-protein core was injected into rabbits. High titer antiserum was obtained as judged by the binding of 125I-labeled keratan sulfate-protein core. Native proteoglycan did not inhibit the interaction of the antiserum with labeled keratan sulfate-protein core. However, the disaccharide obtained from chondroitin 4-sulfate by the action of chondroitinase ABC, 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose, inhibited the interaction 50% at a concentration of 500 microM. The corresponding 6-sulfated and nonsulfated disaccharides at the same concentration gave 15% and 10% inhibition, respectively. Chondroitinase-digested proteoglycan from Swarm rat chondrosarcoma was strongly inhibitory, while the hyaluronidase-digested chondrosarcoma proteoglycan exhibited no detectable inhibition. Evidently, the antiserum raised against chondroitinase ABC-digested bovine nasal cartilage proteoglycan contains antibodies which recognize the unsaturated uronic acid residue linked to N-acetylgalactosamine 4-sulfate. These antibodies will be valuable for identifying and quantitating chondroitin 4-sulfate-containing proteoglycans in tissues.
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PMID:Immunological determinants of proteoglycans. Antibodies against the unsaturated oligosaccharide products of chondroitinase ABC-digested cartilage proteoglycans. 615 67

Interactions between the epithelial and lymphocytic components of the thymus are required for T cell maturation, yet the molecular bases for these interactions remain elusive. In the development and function of other endodermally derived organs, glycosaminoglycan-containing proteins are known to play a critical role. In contrast, virtually nothing is known about the macromolecules that are major constituents of thymic interstitial spaces. For these reasons, we undertook metabolic labeling studies in vitro with D-(6-3H)glucosamine and 35SO4(-2) to begin to characterize systematically the relative amounts and types of glycosaminoglycans made by enriched subpopulations of cells within the thymus. Hydrocortisone, which depletes the thymus of 90% of its lymphocytes, was used both to enrich for epithelium-derived glycoconjugates and to determine if significant alterations in glycoconjugate metabolism accompany drug-induced premature thymic involution. Results indicate: 1) glycosaminoglycans account for a substantial proportion of the total glycoconjugates synthesized by both thymocytes and epithelium; 2) Glycosaminoglycans show a tissue-specific distribution. Hyaluronic acid is the major glycosaminoglycan synthesized by thymic epithelium, whereas it accounts for less than 15% of the total glycosaminoglycans made by thymocytes; 3) Similar proportions of sulfated glycosaminoglycans are made by thymic epithelium and thymocytes. Chondroitin sulfates predominate (75 to 90%) over heparan sulfates (10 to 25%). Chondroitin sulfates from both nonstimulated thymocytes and epithelium are nearly exclusively sulfated at the 4-position of their N-acetylgalactosamine residues; 4) The major high m.w. glycoconjugate of thymocytes, however, is nonsulfated and is resistant to pronase, hyaluronidase, chondroitinase ABC, nitrous acid, keratanase, and neuraminidase; 5) Although hydrocortisone treatment causes a dramatic inhibitory effect on the incorporation of radioactivity into smaller oligosaccharide side-chains by "cortisone-resistant" thymocytes, the drug exerts negligible effects on the metabolism of glycoconjugates by epithelium. These data, which quantify and categorize the complex arrays of glycoconjugates synthesized by the major cell types of the thymus, establish the necessary foundations for further investigations into the functional roles of these glycoconjugates in thymic epithelium-induced maturation of T lymphocytes.
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PMID:Biosynthesis of glycosaminoglycans by epithelial and lymphocytic components of murine thymus. 660 Nov 42

Glycosaminoglycans synthesized in polymorphonuclear (PMN) leucocytes isolated from blood (peripheral PMN leucocytes) and in those induced intraperitoneally by the injection of caseinate (peritoneal PMN leucocytes) were compared. Both peripheral and peritoneal PMN leucocytes were incubated in medium containing [35S]sulphate and [3H]glucosamine. Each sample obtained after incubation was separated into cell, cell-surface and medium fractions by trypsin digestion and centrifugation. The glycosaminoglycans secreted from peripheral and peritoneal PMN leucocytes were decreased in size by alkali treatment, indicating that they existed in the form of proteoglycans. Descending paper chromatography of the unsaturated disaccharides obtained by the digestion of glycosaminoglycans with chondroitinase AC and chondroitinase ABC identified the labelled glycosaminoglycans of both the cell and the medium fractions in peripheral PMN leucocytes as 55-58% chondroitin 4-sulphate, 16-19% chondroitin 6-sulphate, 16-19% dermatan sulphate and 6-8% heparan sulphate. Oversulphated chondroitin sulphate and oversulphated dermatan sulphate were found only in the medium fraction. In peritoneal PMN leucocytes there is a difference in the composition of glycosaminoglycans between the cell and the medium fractions; the cell fraction was composed of 60% chondroitin 4-sulphate, 5.5% chondroitin 6-sulphate, 16.8% dermatan sulphate and 13.9% heparan sulphate, whereas the medium fraction consisted of 24.5% chondroitin 4-sulphate, 28.2% chondroitin 6-sulphate, 33.7% dermatan sulphate and 10% heparan sulphate. Oversulphated chondroitin sulphate and oversulphated dermatan sulphate were found in the cell, cell-surface and medium fractions. On the basis of enzymic assays with chondro-4-sulphatase and chondro-6-sulphatase, the positions of sulphation in the disulphated disaccharides were identified as 4- and 6-positions of N-acetylgalactosamine. Most of the 35S-labelled glycosaminoglycans synthesized in peripheral PMN leucocytes were retained within cells, whereas those in peritoneal PMN leucocytes were secreted into the culture medium. Moreover, the amount of glycosaminoglycans in peritoneal PMN leucocytes was significantly less than that in peripheral PMN leucocytes. Assay of lysosomal enzymes showed that these activities in peritoneal PMN leucocytes were 2-fold higher than those in peripheral PMN leucocytes.
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PMID:Comparative study on glycosaminoglycans synthesized in peripheral and peritoneal polymorphonuclear leucocytes from guinea pigs. 669 21

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.
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PMID:Chemical structure of urinary dermatan sulfate excreted by a patient with the Hunter syndrome. 677 45


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