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)

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

Mucopolysaccharidosis type IVA (Morquio A) is caused by a deficiency of N-acetylgalactosamine-6-sulfatase (GALNS), an enzyme capable of cleaving the sulfate group from both N-acetylgalactosamine-6-sulfate and galactose-6-sulfate. We describe here a two-generation Morquio A family with two distinct clinical phenotypes. The two probands from the second generation showed intermediate signs of the disease whereas their affected mother, aunt and two uncles had only very mild symptoms. Galactose-6-sulfatase (GALS) activity in leukocytes and fibroblasts of the affected family members was clearly deficient. Molecular genetic analysis of the GALNS gene revealed that two different point mutations segregate in the family, which correlated well with the clinical phenotype. The probands with intermediate symptoms were compound heterozygotes for the mutations R259Q and R94G, the latter one being inherited from the unaffected father. The mother and her affected siblings with the unusually mild phenotype were proven to be homozygous for the novel missense point mutation R259Q.
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PMID:Clinical, biochemical and molecular findings in a two-generation Morquio A family. 966 54

Types and distribution patterns of glycoconjugates in antral ovarian follicles were investigated in the buffalo, using periodic-acid Schiff (PAS), high iron diamine (HID), low ion diamine (LID) and lectin histochemical staining methods. HID and LID staining procedures were preceded in some cases by digestion with testicular hyaluronidase, Streptomyces hyaluronidase, chondroitinase ABC and heparitinase (heparinase III). Lectin staining was performed with the use of 12 horseradish peroxidase (HRP) lectin conjugates. Some lectin staining procedures were preceded by neuraminidase digestion and saponification. Large amounts of isomeric chondroitin sulphates and a minor quantity of heparan sulphate and hyaluronic acid and/or chondroitin were found in follicular fluid. Lectin staining of buffalo follicular fluid revealed glycoconjugates with different glucidic determinants such as beta-N-acetylgalactosamine, beta-galactose-(1-3)-N-acetylgalactosamine, beta-galactose-(1-4)-N-acetylglucosamine, N-acetylglucosamine, alpha-fucose and alpha-glucose/alpha-mannose, and sialic acid residues. Glycosaminoglycans were absent in the zona pellucida of oocytes in small antral follicles. Acidic glycoconjugates in the zona pellucida were caused by sulphated groups and sialic acid residues. Our data show few internal glucidic residues, such as N-acetylglucosamine in the buffalo zona pellucida but many subterminal beta-N-acetylgalactosamine, alpha- and beta-galactose determinants masked by sialic acids. These findings demonstrate that buffalo follicular fluid has a very heterogeneous composition that is similar to that found in small and large bovine follicles. No differences in composition of the follicular fluid were observed in the follicles examined.
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PMID:Glycoconjugates in small antral ovarian follicles of the river buffalo (Bubalus bubalis L.). 971 61

Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-D-galactose (delta Di-OS), 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (delta Di-6S) and 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (delta Di-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of delta Di-OS/delta Di-6S/delta Di-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.
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PMID:Isolation and identification of chondroitin sulfates from the mud snail. 987 94

We examined the presence of sialyl glycoconjugates in specific granules from murine bone marrow eosinophils. Lectin cytochemistry using Maackia amurensis lectin II (MAL II) specific for sialyl alpha-2,3 galactose residues demonstrated positive labeling in both immature and mature specific granules. Pretreatment with Clostridium neuraminidase or keratanase II eliminated the positive labeling of MAL II in the specific granules. High iron diamine-thiocarbohydrazide-silver proteinate physical development (HID-TCH-SP-PD) staining, which is specific for sulfated glycoconjugates, also positively labeled immature specific granules lacking crystalloids but not mature granules with crystalloids. Pretreatment with a combination of chondroitinase ABC and keratanase, or a combination of chondroitinase ABC and keratanase II, eliminated the positive labeling obtained with HID-TCH-SP-PD. These results indicate that the sialyl residues detected by MAL II are expressed as terminal sugar residues of keratan sulfate proteoglycan, which appears to be of the corneal type in view of its sensitivity to keratanase and keratanase II. (J Histochem Cytochem 47:481-488, 1999)
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PMID:Keratan sulfate glycosaminoglycans in murine eosinophil-specific granules. 1008 49

We show here that cell surface glycosaminoglycans (GAGs) are involved in the binding of stromal cell-derived factor (SDF)-1alpha to CD4(+)lymphoid CEM or monocytic U937 cells, inasmuch as pretreating the cells with heparitinase or chondroitinase inhibits SDF-1alpha binding by 40-41% and 31-35%, respectively. Soluble heparin or chondroitin sulfate partially but significantly inhibits SDF-1alpha binding to the cells by 45-52% and 42-56%, respectively, while dextran has no significant effect. Taken together, these results indicate the role of GAGs in SDF-1alpha attachment to the cells. However, the effects of heparitinase and chondroitinase as well as those of heparin and chondroitin sulfate are not additive, which suggests that SDF-1alpha may attach to the cells through different GAGs, and also through other ligands. Soluble mannan also inhibits SDF-1alpha binding to the cells by 30-33%. Additivity between this effect and that of heparin or chondroitin sulfate is observed. Therefore, beside GAGs, mannose-containing species may also be involved in SDF-1alpha attachment to the cells. Accordingly, SDF-1alpha specifically binds to heparin-agarose and mannose-divinylsulfone agarose affinity matrices, and these interactions are inhibited respectively by soluble heparin, chondroitin sulfate, and mannan. We have previously shown that gp120 of X4 strain HIV-1LAI presents specific carbohydrate-binding properties for mannosylated derivatives, including mannan, and for GAGs including heparin. The present data therefore indicate that, in the same manner as HIV-1 Env, SDF-1alpha can interact with GAGs and glycans at the cell surface.
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PMID:Glycan and glycosaminoglycan binding properties of stromal cell-derived factor (SDF)-1alpha. 1057 Feb 20

We show that cell surface glycans, sialic acid and mannose-containing species, are involved beside glycosaminoglycans (GAGs), heparan sulfate and chondroitin sulfate in the binding of full length (1--68) RANTES not only to CCR5 positive human primary lymphocytes or macrophages but also to CCR5 negative monocytic U937 cells. Pretreating the cells with neuraminidase, heparitinase, chondroitinase or adding soluble glycans such as mannan or GAGs (heparin or chondroitin sulfate), significantly inhibited RANTES binding. Such effects were not observed with truncated (10--68) RANTES. Heat-denaturation of (1--68) RANTES strongly decreased its binding to the cells, demonstrating involvement of the three-dimensional structure. Accordingly, full length, but not truncated (10--68) RANTES, specifically bound to soluble mannan as well as to mannose-divinylsulfone-agarose affinity matrix and to soluble heparin or chondroitin sulfate as well as to heparin-agarose. Soluble heparin exerts, depending on its concentration, inhibitory or enhancing effects on RANTES binding to mannose-divinylsulfone-agarose, which indicates that RANTES interaction with glycans is modulated by GAGs. These data demonstrate that full length RANTES, but not its (10--68) truncated counterpart, interacts with glycans and GAGs, in soluble forms or presented either by affinity matrices or CCR5 positive as well as CCR5 negative cells.
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PMID:Glycans are involved in RANTES binding to CCR5 positive as well as to CCR5 negative cells. 1134 72

Galactose mutarotase plays a key role in normal galactose metabolism by catalyzing the interconversion of beta-D-galactose and alpha-D-galactose. Here we describe the three-dimensional architecture of galactose mutarotase from Lactococcus lactis determined to 1.9-A resolution. Each subunit of the dimeric enzyme displays a distinctive beta-sandwich motif. This tertiary structural element was first identified in beta-galactosidase and subsequently observed in copper amine oxidase, hyaluronate lyase, chondroitinase, and maltose phosphorylase. Two cis-peptides are found in each subunit, namely Pro(67) and Lys(136). The active site is positioned in a rather open cleft, and the electron density corresponding to the bound galactose unequivocally demonstrates that both anomers of the substrate are present in the crystalline enzyme. Those residues responsible for anchoring the sugar to the protein include Arg(71), His(96), His(170), Asp(243), and Glu(304). Both His(96) and His(170) are strictly conserved among mutarotase amino acid sequences determined thus far. The imidazole nitrogens of these residues are located within hydrogen bonding distance to the C-5 oxygen of galactose. Strikingly, the carboxylate group of Glu(304) is situated at approximately 2.7 A from the 1'-hydroxyl group of galactose, thereby suggesting its possible role as a general acid/base group.
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PMID:High resolution X-ray structure of galactose mutarotase from Lactococcus lactis. 1190 40


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