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:3.1.6.12 (chondroitinase)
2,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A significant decrease in total carbohydrates and particularly in mannose, galactose and sialic acid has been observed in vitamin A-deficient rat liver lysosomal membrane. These alterations adversely affect the membrane permeability and structure-linked latency of the lysosomal enzymes. Significant reduction in the pH-dependent in vitro binding of the lysosomal arylsulfatase B to the highly purified membrane has been observed in vitamin A deficiency. This is attributed to the decrease in electro-negativity, mainly due to the observed reduction in negatively-charged sialic acid residues on the outer side of the membrane. Similar reduction in sialic acid content on the inner side of the membrane affects the microenvironment in the lysosomes. Intralysosomal pH, measured by computing the proteolytic activity of lysed lysosomes and of phagolysosomes, endocytosed with denatured 131I-labelled human serum albumin, is slightly consistently higher in vitamin A-deficient groups compared to that in control alone. This is reflected in the low rate of degradation of the entrapped proteins in vitamin A deficiency. The possible physiological significance of the observations is discussed with special reference to the loss of surface carbohydrates, particularly sialic acid, in vitamin A-deficient rats.
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PMID:Alterations in surface carbohydrates and in some functional properties of liver lysosomal membrane in vitamin A-deficient rat. 721 69

1. Proteoglycan subunits isolated by standard procedures from bovine nasal cartilage, previously incubated in the presence of [32P]phosphate contain [32]-phosphate ester groups as a regular structural component. 2. Contamination of the proteoglycan subunit with 32P-labeled nucleic acids could be excluded by repeated cesium chloride density gradient centrifugation under associative and dissociative conditions, lanthanum chloride precipitation, gel filtration and by the resistance of the proteoglycan subunit associated 32P to phosphoric diester hydrolases. 3. The [32P]phosphate ester groups are associated to the chondroitin sulfate peptide fraction obtained by proteolytic digestion of the proteoglycan subunit molecule. Degradation of the chondroitin sulfate peptide by chondroitinase ABC resulted in a 32P-labelled oligosaccharide peptide fraction, that contains xylose, galactose, glucuronic acid and inorganic phosphate in a molar ratio 1 : 2 : 1 : 0.12. 4. 32P radioactivity is released as inorganic phosphate by treatment of the 32P-labelled oligosaccharide peptide with acid phosphatase or alkali.
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PMID:Phosphate ester groups in proteoglycans from bovine nasal cartilage. 722 19

Isoelectric focusing of homogenous arylsulfatase B from human placenta pointed to the presence of enzymatically active and inactive forms of high pI (pH 9-8) and of lower pI (pH 6.5-5.5). Glycan chain analysis performed with the use of a Glycan Differentiation Kit showed that basic forms of arylsulfatase B from human placenta contained mostly high mannose/hybrid type glycans, with 6-O-L-fucose bound to the innermost N-acetylglucosamine residue, whereas acidic forms of the enzyme contained complex type glycans containing fucose and sialic acid. However, the latter forms constitute a small percentage of the total carbohydrate component. Lectin affinity chromatography of the native enzyme confirmed the presence of a core fucose and a sialic acid.
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PMID:Preliminary characterization of the oligosaccharide component of arylsulfatase B from human placenta. 765 60

Five major hexasaccharide alditols were isolated from the carbohydrate-protein linkage region of bovine aorta dermatan sulfate peptidoglycans after reductive beta-elimination and subsequent chondroitinase ABC digestion. These molecules account for at least 55.3% of the total linkage region. Their structures were analyzed by enzymatic digestion in conjunction with high performance liquid chromatography, electrospray ionization mass spectrometry, and 500-MHz one- and two-dimensional 1H NMR spectroscopy. Three of these compounds have the conventional hexasaccharide core; delta HexA alpha 1-3Gal-NAc beta 1-4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl-ol. One is nonsulfated, and the other two are monosulfated on C6 or C4 of the GalNAc residue. They represent at least 6.3, 5.2, and 28.8% of the total linkage region, respectively. The other two compounds have the following hitherto unreported hexasaccharide core with an internal iduronic acid residue in common; delta HexA alpha 1-3GalNAc beta 1-4IdoA alpha 1-3Gal beta 1-3Gal beta 1-4Xyl-ol. One is monosulfated on C4 of the GalNAc, and the other is disulfated on C4 of the GalNAc and of the galactose residue substituted by the iduronic acid residue. These two compounds account for 35% of the five isolated hexasaccharide alditols and at least 4.3 and 10.7% of the total linkage region, respectively. The latter two structures form a striking contrast to the currently accepted conception that heparin, heparan sulfate, and chondroitin/dermatan sulfate share the common linkage tetrasaccharide core GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl. The biological significance of the isolated structures is discussed in relation to the biological functions and the biosynthetic mechanisms of dermatan sulfate.
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PMID:Structural studies on the hexasaccharide alditols isolated from the carbohydrate-protein linkage region of dermatan sulfate proteoglycans of bovine aorta. Demonstration of iduronic acid-containing components. 770 59

This paper describes low-density mucus glycoconjugates released from feline trachea by dirhamnolipid (DRL), a toxin from Pseudomonas aeruginosa. Mucus glycoconjugates in feline tracheas were radiolabeled in vivo with 3H-proline and 14C-glucose. Control mucus and that released by 200 micrograms/ml DRL were dissolved in guanidine hydrochloride buffer (GuHCl) and chromatographed on Sepharose CL-2B. Molecules eluting in the void volume (V0) of the column were isolated by isopycnic density gradient centrifugation in CsCl/GuHCl. All samples gave peaks of radiolabeled and periodic acid/Schiff (PAS)-reactive material at rho = approximately 1.50 and approximately 1.60 g/ml, but DRL-stimulated samples contained low-density material (rho < 1.32 g/ml), also PAS-reactive and radiolabeled. Control secretions incubated with DRL in vitro did not form low-density material. In Triton X-100 (1% vol/vol), a nonionic detergent, low-density material behaved as smaller molecules, running in the partially included volume (Vi) of the column of Sepharose CL-2B, but still in the V0 of Sephacryl S-300. Incubation with chondroitinase ABC, heparinase II and III, and keratanase failed to change its elution profile on S-300, evidence against glycosaminoglycans; but proteolysis with trypsin or proteinase K gave two peaks, peptide fragments near the totally included volume of the column and glycopeptides in V0. The V0 glycopeptides banded between 1.50 and 1.55 g/ml in a CsCl gradient and eluted as a single peak in the Vi of Sephacryl S-400, suggesting a distinct homogeneous glycopeptide, smaller than those from normal mucins. The main 14C-labeled sugars in this glycopeptide were fucose, glucosamine, galactosamine, and galactose, consistent with a mucin. Thus, DRL releases stable but noncovalent complexes containing one or more distinct mucinlike glycoconjugates, probably combined with lipids and peptides. We discuss their possible relevance to airway diseases, including cystic fibrosis.
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PMID:Mucus glycoconjugate complexes released from feline trachea by a bacterial toxin. 787 96

In a recent study (D. J. Culp, D. K. P. Lee, D. P. Penney, and M. G. Marin. Am. J. Physiol. 263: L264-275, 1992), we reported that primary cultures of cat tracheal gland cells expressed histological, ultrastructural, and immunological characteristics of mucous cells when cultured on floating gels of rat tail collagen (released-gel cultures) compared with cells cultured on glutaraldehyde-fixed collagen gels (fixed-gel cultures). We therefore collected culture medium from gland cells grown under both culture conditions for determination and comparison of glycoconjugates with characteristics of mucin glycoproteins. Cells were cultured in the presence of [3H]glucosamine, and material of high molecular weight and density (HMD material) was isolated. HMD material from both culture conditions were each resistant to heparitinase and heparinase, whereas 72 and 25% of the radiolabel in released-gel and fixed-gel HMD material, respectively, was resistant to chondroitinase ABC. Material resistant to chondroitinase ABC was analyzed further. Both samples contained a single broad glycoprotein band [relative molecular weight (M(r)) > 250,000] after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and had amino acid profiles similar to airway mucin. The sample from fixed-gel cultures had nearly equal amounts of carbohydrate and protein, was highly enriched in N-acetylglucosamine, contained mannose, displayed little blood group A immunoreactivity, and had few O-linked oligosaccharides. Conversely, the sample from released-gel cultures contained 80% carbohydrate, was composed of monosaccharides characteristic of airway mucins, displayed blood group A immunoreactivity, and contained oligosaccharides O-linked via N-acetylgalactosamine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mucinlike glycoproteins from cat tracheal gland cells in primary culture. 821 86

The deduced amino acid sequence of an estrogen-dependent sheep oviductal glycoprotein (M(r) 90,000-116,000) revealed the presence of several potential sites for glycan substitution on a protein backbone of M(r) approximately 66,500, and identity with chitinases. In order to further define the nature of the secreted glycoprotein, the objectives of the present study were 1) to devise a method to significantly enrich for the glycoprotein from oviductal secretions, 2) to biochemically characterize the glycoprotein by use of lectin blotting and enzymatic and chemical digestion, and 3) to determine whether unfractionated and enriched fractions containing the glycoprotein have chitinase activity. Oviducts were obtained from ovariectomized ewes treated with estradiol for 6 days and explant-cultured for 24 h. The oviductal glycoprotein was enriched approximately 80-85% from explant culture media by Maackia amurensis agglutinin (MAA) lectin affinity chromatography. Enriched fractions containing the oviductal protein were separated on SDS gels, transferred to polyvinyl difluoride, and probed with digoxigenin-labeled lectins. Lectin blotting revealed that the glycoprotein contained the carbohydrate moieties N-acetylgalactosamine, N-acetylglucosamine, galactose, fucose, and sialic acid both in alpha(2,3) and alpha(2,6) linkages, typical of sialomucins. Enzymatic digestion with neuraminidase and N-glycanase indicated that approximately 20% and approximately 6% of the molecular weight of the oviductal glycoprotein can be accounted for by sialic acid and N-linked glycans, respectively. The oviductal glycoprotein was resistant to digestion with O-glycanase alone and chondroitinase ABC, with the latter indicating that it was not a proteoglycan. Treatment with trifluoromethanesulfonic acid resulted in a deglycosylated product of M(r) approximately 66,000 immunoreactive with antibodies to the oviductal glycoprotein. No chitinase activity could be detected for unfractionated culture medium proteins or enriched fractions containing the M(r) 90,000-116,000 oviductal glycoprotein when the substrate methylumbelliferyl chitotriose was used. These data show that 1) MAA lectin chromatography can significantly enrich for the M(r) 90,000-116,000 glycoprotein from oviductal secretions, 2) the secreted glycoprotein contains saccharide residues typical of sialomucins, and 3) despite primary amino acid sequence identity, the oviductal glycoprotein does not share an enzymatic relationship with chitinases.
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PMID:An estrogen-dependent sheep oviductal glycoprotein has glycan linkages typical of sialomucins and does not contain chitinase activity. 856 10

We have previously suggested that sulfated polysaccharides could be used in a vaginal formulation to inhibit infection by human immunodeficiency virus (HIV-1). This supposition was based on studies in which we developed and employed an in vitro model to simulate the mechanism of HIV-1 transmission during coitus. We found that adhesion of mononuclear cells to epithelia was the initial step in infection and speculated that blocking adhesion would prevent HIV-1 transmission. We observed that certain sulfated polysaccharides prevented adhesion of lymphoma cell lines to epithelial cell lines, which were derived from the genital tract, in concentrations of a few milligrams per milliliter; and we theorized that sulfated polysaccharides could thus be used as active ingredients in a topical "microbicide." In the present in vitro study, evidence is presented that a number of sulfated polysaccharides, including carrageenan, dextran sulfate, heparin, fucoidan, and pentosan polysulfate, are capable of blocking infection by mechanisms other than adhesion at concentrations of a thousand times lower than the dosages that are needed to block cell adhesion. One of these compounds, iota carrageenan, is capable not only of blocking infection of epithelia at concentrations of 1-2 micrograms, but of blocking adhesion to a far greater extent than the other sulfated polysaccharides tested. For this reason, as well as for considerations of safety, stability, and gelling properties, we suggest that iota carrageenan may be the best choice of the sulfated polysaccharides tested for use as a vaginal microbicide. The same in vitro model was employed to decipher the cell surface molecules involved in lymphocyte-to-epithelial adhesion. To accomplish this, we screened for the presence of cell adhesion molecules (CAMs), carbohydrates, proteoglycans, and carbohydrate-binding sites. HIV-1-infected lymphocytic cells expressed a CAM profile typical of activated, infected cells (e.g., HLA-DR+, CD4-, LFA-1+, ICAM-1+, LFA-3+, CD2+) whereas epithelia expressed few CAMs (LFA-3, ICAM-1, VLA-5, CD44, CD26, sLEX). Both cell types expressed heparan sulfate and chondroitin sulfate proteoglycans. A variety of sugars (mannose, fucose, galactose, Nac-galactosamine, Nac-glucosamine) were also present, but these cells expressed few carbohydrate-binding sites; lymphocytes bound beta-galactose. We were unable to block the adhesion with anti-CAM antibodies or with exogenous sugars. When enzymes were used against sulfated cell surface molecules, chondroitinase was found to block the adhesion. Our evidence suggests that this CAM-independent adhesion may be a lectin-glycosaminoglycan interaction.
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PMID:Sulfated polysaccharides inhibit lymphocyte-to-epithelial transmission of human immunodeficiency virus-1. 883 15

A glycan chain analysis of the total oligosaccharide pool derived from rat liver arylsulfatase B was carried out by. P4 Gel Permeation Chromatography and sequential exoglycosidase digestion. It was found that 71% of rat liver arylsulfatase B oligosaccharides were sialylated. The relative contribution of particular structures in the total glycan pool was as follows: sialylated biantennary complex type glycans with terminal galactose--65%, high-mannose type glycans--15%, biantennary complex type glycans with core fucose and terminal N-acetylglucosamine--5%, O-linked oligosaccharides--3.5%.
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PMID:Characterization of the oligosaccharide component of arylsulfatase B from rat liver. 936 Jul 6

An assay was developed, using two similar formats, to simultaneously measure both the lysosomal targeting receptor binding and enzyme activity of the recombinant human enzyme N-acetylgalactosamine-4-sulfatase. This assay also has potential application for all phosphorylated lysosomal enzymes that contain mannose-6-phosphate residues. The receptor was either purified from fetal bovine sera then adsorbed, or produced in situ by growing and fixing diploid human fibroblast-like cells, to a solid phase. The enzyme substrate was 4-methylumbelliferyl sulfate which fluoresces after cleavage of the sulfate moiety. Both the precursor and mature forms of the recombinant enzyme were used to demonstrate the specificity and usefulness of the assay. The assay is rapid and sensitive and has a wide dynamic range. Association between the receptor and the mannose-6-phosphate residues was abrogated in the presence of a competitive inhibitor, mannose 6-phosphate. However, partial activity was still measured when the mature enzyme was incubated in the presence of mannose 6-phosphate when using the fixed fibroblast format. This would indicate that the recombinant enzymes contain at least one terminal sugar moiety other than mannose 6-phosphate which can recognize receptors on the surface of human fibroblast-like cells. Other possible applications of this assay are also discussed.
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PMID:A quantitative mannose 6-phosphate receptor-based in vitro assay for recombinant human N-acetylgalactosamine-4-sulfatase. 965 68


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