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:3.2.1.36 (hyaluronidase)
4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies on rabbit thrombomodulin (TM) revealed that certain anticoagulant activities expressed by TM depend on the presence of an acidic domain tentatively identified as a sulfated galactosaminoglycan (Bourin, M.-C., Ohlin, A.-K., Lane, D., Stenflo, J., and Lindahl, U. (1988) J. Biol. Chem. 263, 8044-8052). The glycan was released by alkaline beta-elimination, isolated by ion-exchange chromatography, and radiolabeled by partial N-deacetylation (hydrazinolysis) followed by re-N-[3H]acetylation. The labeled product behaved like standard chondroitin sulfate on ion-exchange chromatography, exhibited a Mr of 10-12 x 10(3) on gel chromatography, and was susceptible to degradation by chondroitinase and testicular hyaluronidase. The major labeled degradation products following digestion of the glycosaminoglycan with chondroitinase were identified, depending on the incubation conditions, either as 4/6-mono-O-sulfated, 4,5-unsaturated disaccharides (delta HexA-GalNAc(S] and N-acetylgalactosamine 4,6-di-O-sulfate (GalcNAc (diS], the latter component accounting for approximately 25% of the total label, or as a major fraction of labeled trisaccharide, with the predominant structure GalNAc(diS)-GlcA-GalNAc(diS). The terminal GalNAc(diS) unit (not substituted at C3) was shown to be more susceptible to N-deacetylation during hydrazinolysis than were the internal GalNAc units (substituted at C3), and thus was more extensively labeled, resulting in over-representation of this unit. It is concluded that rabbit TM is a chondroitin sulfate proteoglycan, which carries a single glycan side chain characterized by an unusual accumulation of sulfate groups at the nonreducing terminus. Metabolically 35S-labeled TM was isolated from cultured rabbit heart endothelial cells and characterized as a chondroitin sulfate proteoglycan which accounted for 1-2% of the total 35S-labeled cell-associated macromolecules. The isolated chondroitin sulfate showed weaker antithrombin-dependent anticoagulant activity, on a molar basis, than the intact TM proteoglycan. The anticoagulant action of TM thus depends on a unique form of functional collaboration between the different constituents of a glycoconjugate.
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PMID:Isolation and characterization of the glycosaminoglycan component of rabbit thrombomodulin proteoglycan. 216 13

An air-liquid interface (biphasic) primary culture system in which guinea pig tracheal epithelial cells maintain morphologic characteristics of differentiated epithelium has been developed in this laboratory. In this report, we compared quantitatively cell populations of 8-day cultures to those of epithelial mucosa in intact trachea. In addition, high molecular weight glycoconjugates released by the cultured cells were isolated and characterized. Quantitative morphometric analysis revealed similar volume densities of ciliated, secretory, basal, and "other" cells in cultures and in intact tracheal surface epithelium, although the cultures tended to have smaller cells and contained fewer basal cells. High molecular weight glycoconjugates released apically by cell cultures and excluded from Sepharose CL-4B columns contained approximately 5% hyaluronic acid but undetectable amounts of other proteoglycans, such as chondroitin sulfate, heparan sulfate, and dermatan sulfate. The hyaluronidase-resistant glycoconjugates exhibited a peak buoyant density at 1.49 g/ml on cesium chloride density gradient centrifugation and were shown to contain mucin-type carbohydrate to peptide linkages (i.e., GalNAc to ser/thr) and an amino acid composition typical of respiratory mucins. The results indicate that this organotypic cell culture system mimics quite closely morphology of mucosal epithelium in intact airways and that the cells release high molecular weight glycoconjugates with biochemical properties of mucin-type glycoproteins. Thus, this in vitro system appears well-suited for studies of mucin secretion and other functions of respiratory epithelial cells.
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PMID:Characterization of guinea pig tracheal epithelial cells maintained in biphasic organotypic culture: cellular composition and biochemical analysis of released glycoconjugates. 230 71

Monoclonal antibodies produced against chick embryo limb bud proteoglycan (PG-M) were selected for their ability to recognize determinants on intact chondroitin sulfate chains. One of these monoclonal antibodies (IgM; designated MO-225) reacts with PG-M, chick embryo cartilage proteoglycans (PG-H, PG-Lb, and PG-Lt), and bovine nasal cartilage proteoglycan, but not with Swarm rat chondrosarcoma proteoglycan. The reactivity of PG-H to MO-225 is not affected by keratanase digestion but is completely abolished after chondroitinase digestion. Competitive binding analyses with various glycosaminoglycan samples indicate that the determinant recognized by MO-225 resides in a D-glucuronic acid 2-sulfate(beta 1----3)N-acetylgalactosamine 6-sulfate disaccharide unit (D-unit) common to antigenic chondroitin sulfates. A tetrasaccharide trisulfate containing D-unit at the reducing end is the smallest chondroitin sulfate fragment that can inhibit the binding of the antibody to PG-H. Decreasing the size of a D-unit-rich chondroitin sulfate by hyaluronidase digestion results in progressive reduction in its inhibitory activity. The results suggest that the epitope has a requirement for a long stretch of a disaccharide-repeating structure for a better fit to the antibody.
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PMID:A monoclonal antibody that specifically recognizes a glucuronic acid 2-sulfate-containing determinant in intact chondroitin sulfate chain. 243 33

We characterized the chemical composition of mucins secreted by ferret tracheal explants and the activities of key mucin glycosyltransferases in ferret tracheal epithelium during a period of rapid postnatal maturation of the mucin-secreting structures. Ferret tracheal explants secrete three major groups of high molecular weight glycoconjugates: (1) those susceptible to bovine testicular hyaluronidase; (2) those resistant to hyaluronidase and exhibiting high density (p greater than or equal to 1.60 g/mL); and (3) those resistant to hyaluronidase and exhibiting low density (1.45 less than or equal to p less than 1.60 g/mL). The hyaluronidase-resistant, low-density glycoconjugates have typical mucin properties and constitute 36% of total glycoconjugates released in newborns but only 8% in adult ferrets. Mucin secretory rate per unit surface area of trachea progressively decreases with age. Mucin amino acid and total carbohydrate contents do not vary; however, the sialic acid content increases, and fucose content as well as blood group A activity of the mucins decreases with age. Four glycosyltransferases involved in mucin biosynthesis [Gal beta 3GalNAc:(GlcNAc-GalNAc)beta 6 N-acetylglucosaminyl-, GalNAc:beta 3 galactosyl-, Gal:alpha 2 fucosyl-, and GalNAc alpha 2----6 neuraminyltransferase] are present in tracheal epithelium of ferrets at all ages. Activities of all but the neuraminyltransferase decrease with age. The relatively greater neuraminyltransferase activity is consistent with increased incorporation of sialic acid into secreted mucins over the same age span. Conversely, diminution of fucosyltransferase relative to galactosyltransferase activity may contribute to the lower fucose content and lower blood group A activity of mucins secreted by mature ferret tracheas.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Developmental changes of ferret tracheal mucin composition and biosynthesis. 261 Dec 42

Colon cancer cells in culture synthesize and secrete mucin glycoproteins, which carry a number of cancer-associated antigens. However, the structures and mechanisms of biosynthetic processing are not well understood. Mucins synthesized and secreted by LS174T human colon cancer cells were compared to those in LS174T xenografts in athymic mice. Mucins radiolabeled with glucosamine or sulfate were purified by gel filtration and cesium chloride density gradient centrifugation. The mucins were of high molecular weight and were resistant to chondroitinase ABC, hyaluronidase and HNO2 treatment. They were, however, susceptible to pronase digestion and mild alkaline treatment. Using radiochemical precursors, the cellular mucin was shown to contain fucose, galactose, N-acetylgalactosamine, N-acetylglucosamine, N-acetylneuraminic acid, and sulfate. Oligosaccharides released by beta-elimination had N-acetylgalactosaminitol as the reduced amino sugar and also unreduced galactosamine, indicating that there is N-acetyl-galactosamine O-glycosidically attached to protein core and also peripheral N-acetyl-galactosamine not directly linked to protein. DEAE-cellulose chromatography of mucins showed two major peaks with both intracellular and secreted mucins, but xenograft mucins also had more acidic components. Sulfate-labeled mucins were shifted to less acidic peaks by neuraminidase digestion, which indicates that the same mucin molecules are both sialylated and sulfated. We conclude that the intracellular mucins of cultured colon cancer cells, those secreted into the medium, and those in nude mouse xenografts are chemically similar, but differ in sialic acid and sulfate content. This experimental model system, LS174T cells maintained in culture and as nude mouse xenografts, may be useful for further biosynthetic and structural studies of colon cancer mucin.
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PMID:Comparison of metabolically labeled mucins of LS174T human colon cancer cells in tissue culture and xenograft. 273 49

The effects of steroid hormones on the synthesis of lactosaminoglycan (LAG)-containing oligosaccharides by mouse uteri are reported. The uterine LAG-containing oligosaccharides were degraded partially by Pseudomonas endo-beta-galactosidase, releasing an oligosaccharide of the apparent structure: Gal beta----N-acetylglucosaminyl(----N-acetylgalactosaminyl)beta 1,3----galactose. A larger fraction of the LAG-containing oligosaccharides bound to pokeweed mitogen than to Datura stramonium lectin, suggesting the presence of highly branched structures. LAG-containing oligosaccharides were resistant to sequential digestion with Pronase, nitrous acid, hyaluronidase, and chondroitinase ABC. These polysaccharides exhibited a Gal:GlcNAc:GalNAc ratio of approximately 1.0:1.0:0.3 and were not fucosylated. The ion-exchange behavior of the LAG-containing oligosaccharides before and after mild acid hydrolysis indicated the presence of sialic acid residues. The LAG-containing glycopeptides were highly resistant to beta-elimination but were released quantitatively by hydrazinolysis, demonstrating an N-linkage to protein. Binding to pokeweed mitogen was markedly enhanced following release of these oligosaccharides from peptides by hydrazinolysis, suggesting that peptide-bound oligosaccharides were partially inaccessible to the lectin. Molecular exclusion chromatography of the oligosaccharides released by hydrazinolysis revealed a broad distribution ranging from Mr 4,000 to 15,000 with a median Mr of approximately 8,000. We extended the above observations by determining how the steroid hormones 17-beta-estradiol (E2) and progesterone affected synthesis of the LAG-containing oligosaccharides in ovariectomized mice. Generally, E2 and a number of E2 agonists stimulated glycoconjugate synthesis; however, chronic E2 treatment or combined treatment with E2 plus progesterone caused the synthesis of most glycosaminoglycans to return to basal levels. In contrast, E2 either alone or in combination with progesterone stimulated synthesis of LAG-containing oligosaccharides in preference not only to glycosaminoglycans but also to other classes of N-linked oligosaccharides. This effect was apparent during both priming and nidatory E2 treatments. Collectively, these data provide the first demonstration of LAG-containing oligosaccharides in uteri and for the hormonally regulated synthesis of lactosaminoglycans. In addition, this is the first demonstration of the ability of steroid hormones to induce the synthesis of certain types of N-linked oligosaccharides in preference to others in the same tissue.
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PMID:Estrogen preferentially stimulates lactosaminoglycan-containing oligosaccharide synthesis in mouse uteri. 312 90

In the distal hypertrophic zone of growth-plate cartilage, the pericellular matrix surrounding individual chondrocytes and the territorial matrix uniting chondrocytes into columnar groups are invaded by metaphyseal endothelial cells prior to osteogenesis. In the present study, lectin-binding glycoconjugates were analyzed in these two matrix compartments of growth-plate cartilage from Yucatan swine. Nine lectin-fluorescein conjugates were tested by a postembedment method on 1-micron-thick, nondecalcified, Epon-embedded sections. Chondrocytes in all cellular zones were surrounded by a pericellular matrix which showed positive binding for peanut agglutinin (PNA), ricin agglutinin (RCA-I), and soybean agglutinin (SBA). Binding by these lectins was sensitive to digestion with hyaluronidase, chondroitinase, and trypsin. Pericellular glyconconjugtes that bind RCA-I and concanvalin A (CONA) after periodic acid oxidation, and which were sensitive to trypsin but not to chondroitinase or hyaluronidase, were present in the hypertrophic cell zone. Within the territorial matrix, binding of lectins specific for galactose, N-acetylgalactosamine, and fucose showed gradients of intensity which became maximal at the last transverse septum. Lectin-binding histochemistry more precisely differentiated the microheterogeneity of glycoconjugate distribution within these two matrix compartments than has been possible with other histochemical techniques. Lectin-binding affinity is a potentially useful technique by which to isolate cartilage matrix macromolecules unique to specific cellular zones of the growth plate.
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PMID:In situ localization of lectin-binding glycoconjugates in the matrix of growth-plate cartilage. 372 44

The major urinary trypsin inhibitor (Mr 44 000), isolated from human urine, contains 35% carbohydrate. In addition to N-acetylglucosamine and neutral sugars (primarily mannose and galactose), the carbohydrate moiety contains hexuronic acid and N-acetylgalactosamine and corresponds to a glycosaminoglycan. This carbohydrate chain is an integral component of the inhibitor: it does not dissociate from the inhibitor when using dissociative conditions such as sodium dodecyl sulfate, guanidinium chloride, or by increasing ionic strength or mixing with cetylpyridinium chloride. This glycosaminoglycan chain is sensitive to chondroitinase ABC or testicular hyaluronidase digestion and corresponds to slightly sulfated chondroitin 4-sulfate or 6-sulfate. After treatment by these enzymes, the urinary inhibitor has a lower molecular mass (Mr 26 000) but still inhibits trypsin.
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PMID:The major human urinary trypsin inhibitor is a proteoglycan. 373 76

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

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


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