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)

Dermatan sulfate-chondroitin sulfate copolymers have been isolated from human umbilical cord as a major galactosaminoglycan component of this tissue. The galactosaminoglycan fraction was obtained from this tissue by papain [EC 3.4.22.2] digestion followed by precipitation with cetylpyridinium chloride in a yield of 700 mg per 100 g of dry tissue. Ethanol fractionation resolved 4-5 subfractions differing in relative content of L-iduronic acid and D-glucuronic acid. No galactosaminoglycan containing either solely L-iduronic acid or D-glucuronic acid was obtained. The copolymeric structure of the material in each subfraction was demonstrated by analysis of oligosaccharide fragments obtained by chondroitinase-AC [EC 4.2.2.5] digestion. All the polymers contained repeating disaccharide units, D-glucuronosyl-N-acetylgalactosamine, D-glucuronosyl-N-acetylgalactosamine 4-sulfate, D-glucuronosyl-N-acetyl-galactosamine 6-sulfate, and L-iduronosyl-N-acetylgalactosamine 4-sulfate, of which D-glucuronosyl-N-acetylgalactosamine 6-sulfate and L-iduronosyl-N-acetylgalactosamine 4-sulfate were predominant. Both iduronic acid- and glucuronic acid-containing units were arranged in clusters. The presence of a considerable amount of nonsulfated disaccharide units was noted. The copolymers show extensive polydispersity in electrophoresis on cellulose acetate and gel chromatography on Sephadex G-200.
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PMID:Dermatan sulfate-chondroitin sulfate copolymers from ambilical cord. Isolation and characterization. 97 51

Dermatan sulfate proteoglycans (DS-PGs) isolated from bovine articular cartilage have been examined for their effects on the adhesive responses of BALB/c 3T3 cells and bovine dermal fibroblasts on plasma fibronectin (pFN) and/or type I collagen matrices, and compared to the effects of the chondroitin sulfate/keratan sulfate proteoglycan monomers (CS/KS-PGs) from cartilage. DS-PGs inhibited the attachment and spreading of 3T3 cells on pFN-coated tissue culture substrata much more effectively than the cartilage CS/KS-PGs reported previously; in contrast, dermal fibroblasts were much less sensitive to either proteoglycan class unless they were pretreated with cycloheximide. Both cell types failed to adhere to substrata coated only with the proteoglycans; binding of the proteoglycans to various substrata has also been quantitated. While a strong inhibitory effect was obtained with the native intact DS-PGs, little inhibitory effect was obtained with isolated DS chains (liberated by alkaline-borohydride cleavage) or with core protein preparations (liberated by chondroitinase ABC digestion). In marked contrast, DS-PGs did not inhibit attachment or spreading responses of either 3T3 or dermal fibroblasts on type I collagen-coated substrata when the collagen was absorbed with pFN alone, DS-PGs alone, or the two in combination. These results support evidence for (a) collagen-dependent, fibronectin-independent mechanisms of adhesion of fibroblasts, and (b) different sites on the collagen fibrils where DS-PGs bind and where cell surface "receptors" for collagen bind. Experiments were developed to determine the mechanism(s) of inhibition. All evidence indicated that the mechanism using the intact pFN molecule involved the binding of the DS-PGs to the glycosaminoglycan (GAG)-binding sites of substratum-bound pFN, thereby inhibiting the interaction of the fibronectin with receptors on the cell surface. This was supported by affinity chromatography studies demonstrating that DS-PGs bind completely and effectively to pFN-Sepharose columns whereas only a subset of the cartilage CS/KS-PG binds weakly to these columns. In contrast, when a 120-kD chymotrypsin-generated cell-binding fragment of pFN (CBF which has no detectable GAG-binding activity as a soluble ligand) was tested in adhesion assays, DS-PGs inhibited 3T3 adherence on CBF more effectively than on intact pFN. A variety of experiments indicated that the mechanism of this inhibition also involved the binding of DS-PGs to only substratum-bound CBF due to the presence of a cryptic GAG-binding domain not observed in the soluble CBF.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Fibronectin-mediated adhesion of fibroblasts: inhibition by dermatan sulfate proteoglycan and evidence for a cryptic glycosaminoglycan-binding domain. 295 85

A chondroitin sulfate-dermatan sulfate proteoglycan was isolated from bovine aorta intima by extraction of the tissue by 4 M guanidine hydrochloride. The proteoglycan was purified by CsCl isopycnic centrifugation followed by gel filtration and ion-exchange chromatography. The proteoglycan had 21.9% protein, 22.1% uronate, 21.4% hexosamine and 10.8% sulfate. Glycosaminoglycan chains obtained from the proteoglycan by beta-elimination were resolved by gel filtration into two fractions, one containing chondroitin 6-sulfate with an approximate molecular weight of 49 000 and the other containing chondroitin 4-sulfate and dermatan sulfate in a proportion of 2:1 with an approximate molecular weight of 37 000. Digestion of the proteoglycan by chondroitinase ABC or AC yielded a protein core with similar composition and behavior in gel filtration and SDS-polyacrylamide gel electrophoresis. An approximate molecular weight of 180 000 was estimated for the core protein. Dermatan sulfate chains with an approximate molecular weight of 10 000 were observed only in the digest of chondroitinase AC. Limited trypsin hydrolysis of the proteoglycan yielded three peptide fragments containing chondroitin 6-sulfate, chondroitin 4-sulfate and dermatan sulfate in varied proportions. A tentative structure for the proteoglycan was suggested.
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PMID:Organization of glycosaminoglycan chains in a chondroitin sulfate-dermatan sulfate proteoglycan from bovine aorta. 308 26

Dermatan sulfate (DS) proteoglycans (PGs) were extracted from human post-burn scar (Sc) tissues with 4M guanidinium chloride and isolated from the extracts by DEAE-cellulose chromatography and by differential ethanol precipitation. The DS.PGs were further purified by Sepharose CL-6B column chromatography. The average molecular weight (Mr) of hypertrophic scar (HSc) tissue DS.PGs was 39,000 based on sedimentation equilibrium measurements. Alkaline borohydride treatment of DS.PGs liberated glycosaminoglycan (GAG) chains and the presence of xylitol indicated that these chains were attached to protein core by xylosyl residues. The average Mr of the DS.GAG chain from HSc and normal scar (NSc) samples were 23,500 and 20,000 respectively. After digestion of the HSc and NSc, DS.PGs with chondroitinase ABC in the presence of proteinase inhibitors, two peptide components with Mr values of 21,500 and 17,000 were detected by SDS-polyacrylamide gel electrophoresis using reducing conditions. Analysis of the protein core fractions derived from NSc and HSc DS.PGs by Sepharose CL-6B column chromatography showed the presence of a single NH2-terminal amino acid (aspartic acid) and also that the fractions with different KAV values had an identical NH2-terminal sequence (A1-A5). The A1-A23 sequence of NSc DS.PG (major fraction, C): NH2Asp-Glu-Ala-O-Gly-Ile-Gly-Pro-Glu-Val-Pro-Asp-Asp-Arg-Asp-Phe-G lu-Pro- Ser-Leu-Gly-Pro-Val was the same as reported for a DS.PG isolated from human fetal membrane (HFM) tissue (Brennan et al., 1984). ELISA inhibition assay using monoclonal antibodies raised in rabbit against the NH2-terminal peptide (containing 15 amino acids) of human fetal membrane tissue were found to cross-react with HSc and NSc DS.PGs. Monoclonal antibodies to bovine skin DS.PGs protein core (Pearson et al., 1983) did not show any cross-reactivity with scar DS.PGs. These results show that the scar DS.PGs described here are different from normal bovine skin DS.PGs in the size and type of the protein core, and that in all the samples, the peptide components have the same NH2-terminal amino acid sequence.
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PMID:Isolation and partial characterization of dermatan sulfate proteoglycans from human post-burn scar tissues. 321 4

The glycosaminoglycan (GAG) contents of hypertrophic scars, normal scars, and human skin from cadavers of matched ages were compared. Cellulose acetate electrophoresis, chondroitinase digestions, and reaction product and infrared analyses were used to characterize the component GAGs. DEAE-cellulose chromatography was used to separate hyaluronic acid (HA) and sulfated GAGs. Chondroitinase analysis was improved under these conditions. HA was determined enzymatically. Results showed an elevation of HA in hypertrophic scar. Dermatan sulfate was the major GAG in both scars and a slightly greater quantity was observed in the hypertrophic scar. Small amounts of chondroitin 4-sulfate and chondroitin 6-sulfate disaccharide constituents were also detected by the chondroitinase assay method and these were also elevated in hypertrophic scar. These results suggest that the GAGs of hypertrophic scar differ from normal scar and normal skin.
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PMID:Glycosaminoglycans of normal and hypertrophic human scar. 669

Epimerization of D-glucuronosyl residues to L-iduronosyl ones during biosynthesis of dermatan sulfate involves an abstraction of the C-5 hydrogen of the target sugar residue. After inversion, a hydrogen from the medium is reinserted into the uronosyl residue. In the present study, microsomal enzyme prepared from cultured embryonic skin fibroblasts was incubated with dermatan or chondroitin in the presence of 3H2O of high specific activity. Incubation resulted in incorporation of tritium on C-5 of uronosyl residues of the substrates. The rate of the reaction was highest for dermatan. Incubation of the products with chondroitinase ABC released essentially all the tritium. Dermatan sulfate and chondroitin sulfate were inactive as substrates, which indicates that epimerization takes place before sulfation. Analyses of the product obtained after incubation of chondroitin in 3H2O-containing medium for different incubation times showed that tritium accumulated first in L-iduronosyl residues. Later, tritium was also found in D-glucuronosyl residues. The reverse situation was observed when dermatan was used as substrate. After extended incubation times, the ratio of D-[3H]glucuronic acid to L-[3H]iduronic acid in both dermatan and chondroitin reached a value of 85/15, which may reflect the equilibrium value. Digestion of labeled chondroitin with chondroitinase AC and oxidation of labeled dermatan with periodate showed that after 96 h of incubation with the epimerase and 3H2O, most of the uronic acid residues had been involved in the reaction. Both products were composed of long blocks of D-glucuronic acid-containing disaccharides interrupted by a few L-iduronic acid-containing disaccharides arranged singly of in clusters of two to three. Reincubation of the 3H-labeled products originating from dermatan or chondroitin with the epimerase resulted in release of tritium, which was linear with time and with increasing protein concentration.
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PMID:Biosynthesis of dermatan sulfate. II. Substrate specificity of the C-5 uronosyl epimerase. 670 27

Crude glycosaminoglycans were prepared from acetone powder of diabetic, toxemic, and normal term placentas. Glycosaminoglycan composition was determined by electrophoresis and densitometric scanning with and without treatment with testicular hyaluronidase and chondroitinase ABC. The identity of individual glycosaminoglycans was confirmed by the nature of their hexosamine. Glycosaminoglycan content was found to be significantly increased in diabetic placentas and increased to a lesser degree in the toxemic placentas. The amount of hyaluronic acid was elevated in both abnormal tissues, and heparan sulfate was slightly higher in diabetes, while unchanged in toxemia. Dermatan sulfate was markedly reduced in the abnormal placentas while chondroitin 4/6 sulfate was unaltered. An attempt was made to correlate the histopathologic changes reported to occur in these conditions with the alterations in the glycosaminoglycans patterns of placentas.
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PMID:Glycosaminoglycan patterns in diabetic and toxemic term placentas. 677 11

Dermatan sulfate was extracted and purified from beef intestinal mucosa. The structure and physicochemical properties were evaluated by different techniques, such as, disaccharide pattern, relative molecular mass, sulfate-to-carboxyl ratio, and electrophoretic profile in agarose electrophoresis. The biological activity was evaluated as heparin cofactor II activity (HCII activity). The purity of dermatan sulfate was carefully evaluated by specific enzymatic cleavage, agarose electrophoresis, and HPLC. Different relative molecular masses of dermatan sulfate, from 25,000 to 2000, were prepared by chemical degradation. The structures and physicochemical properties were checked to exclude a possible desulfation process. The HCII activities were evaluated for different relative molecular mass of dermatan sulfate. The capacity of chondroitinase ABC to cleave different relative molecular masses of dermatan sulfate was also studied. Native dermatan sulfate was fractionated according to charge density. Different fractions were obtained and analysed for disaccharide pattern, relative molecular mass, sulfate-to-carboxyl ratio, and HCII activities.
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PMID:Dermatan sulfate from beef mucosa: structure, physicochemical and biological properties of fractions prepared by chemical depolymerization and anion-exchange chromatography. 818 Oct 3

Heparin was extracted and purified from beef intestinal mucosa. The two components, fast moving heparin and slow moving heparin were purified by selective precipitation as barium salts. Heparan sulfate was extracted and purified from beef spleen. Dermatan sulfate was purified from beef intestinal mucosa and chondroitin sulfate from bovine trachea. The purity of the purified glycosaminoglycans was evaluated by agarose-gel and cellulose polyacetate electrophoresis and by specific optical rotation. The relative molecular masses of glycosaminoglycans were estimated by high performance-size exclusion chromatography and the sulfate to carboxyl ratio by titrimetric analysis. The disaccharide pattern of heparin, fast moving and slow moving heparins and heparan sulfate were determined by specific enzymatic cleavage using heparinase I, II and III; the disaccharide composition of dermatan sulfate and chondroitin sulfate was evaluated by cleavage by chondroitinase ABC. The disaccharides obtained by enzymatic cleavage were qualitatively and quantitatively analysed by strong anion exchange-high performance liquid chromatography. The sulfate to carboxyl ratios of glycosaminoglycans were also determined by this technique and compared with the values obtained by titrimetric analysis.
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PMID:Extraction, purification and evaluation of structures and physico-chemical properties of glycosaminoglycans. 835 79

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.
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PMID:Structural diversity of mammalian hepatic dermatan sulfates. 835 80


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