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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)
The structure of adult bovine articular cartilage high density proteoglycans (PG-I) was studied by degradation with Pronase,
chondroitinase
ABC, and alkaline borohydride treatments and fractionation and analysis of the products. The keratan sulfate (KS) peptides were rich in glutamic acid, proline, and serine and had a low glycine content. The chondroitin sulfate (CS) peptides had a high content of serine, glycine, and glutamic acid and a much lower proline content than the KS peptides. The data indicate that the KS and CS chains occur in more distinct regions of the protein core(s) than in bovine nasal cartilage PG. After alkaline borohydride treatment there was an almost quantitative conversion of xylose to xylitol and galactosaminitol was the only hexosaminitol detected in KS fractions. The results obtained indicated that the alkali-labile bonds linking the CS and KS chains are the same as those reported to occur in other cartilage PGs. The Mr of the KS chains calculated from the
glucosamine
and galactosaminitol contents gave values of 6,000-7,000, although gel chromatography and light scattering measurements indicated considerable heterogeneity. The KS and CS chains were quantitatively precipitated by cetylpyridinium chloride and the KS and a portion (15%) of the CS chains were found to be soluble in 1% cetylpyridinium chloride. The abnormal solubility properties of the CS chains in the presence of 1% cetylpyridinium chloride is thought to be due to their low sulfate content. The molecular weight of the remainder of the CS chains, based on the ratio of xylitol to galactosamine, varied from 6,500 to 16,000. The low Mr CS chains were rich in 6-sulfated disaccharides whereas the higher Mr chains had a higher content of 4-sulfated disaccharides. The ratio of galactose to xylitol also varied with Mr. These results indicate similarities in the structure of the adult bovine articular cartilage PG-Is to other cartilage high density PGs. The heterogeneities observed in the composition of the KS and CS chains, and their occurrence in relatively distinct regions of the protein core(s) indicate, however, that there is still much to be learned about the structure of these complex macromolecules.
...
PMID:On the structure of bovine articular cartilage high density proteoglycans. Isolation of the keratan sulfate and chondroitin sulfate side chains. 623 5
Bovine cumulus-oocyte complexes from small (1-5 mm) follicles were cultured for 24 h in 0.25 ml minimum essential medium supplemented with 10% fetal bovine serum and 20 microCi [3H]
glucosamine
. Treatment groups consisted of supplementing the culture medium with no hormone (control), 0.5 IU/ml follicle-stimulating hormone (FSH) or 10 mM 8-Br-adenosine cyclic monophosphate (cAMP). After culture, the complexes were fixed for light and scanning electron microscopy. Electron photomicrographs revealed that complexes induced to expand with FSH or cAMP contained a copious glycosaminoglycan (GAG) matrix extending between and around the cumulus cells. Control complexes did not exhibit expansion or an extracellular matrix. The radiolabeled GAG material was isolated for chemical identification. Chemical analyses included: (1) electrophoresis of GAG material, (2) electrophoresis of GAG material after enzyme or nitrous acid treatment, (3) thin-layer chromatography of GAG hydrolysates. The results from electrophoresis showed that the radiolabeled GAG co- migrated with hyaluronic acid. The GAG material was resistant to
chondroitinase
ABC and nitrous acid degradation but was digested by hyaluronidase. Complexes treated with FSH and cAMP incorporated higher (P less than 0.1 and P less than 0.025 respectively) amounts of [3H]
glucosamine
into hyaluronic acid than control cultures. Thin-layer chromatography identified the primary amino sugar of the GAG to be
glucosamine
. These data collectively showed that the radioactive GAG produced by bovine cumulus-oocyte complexes was hyaluronic acid.
...
PMID:Glycosaminoglycans in bovine cumulus-oocyte complexes: morphology and chemistry. 629 Feb 89
Bovine granulosa cells from small (1-9 mm) or large (10-20 mm) follicles were incubated in a chemically defined medium containing 5 muCi/ml [3H]
glucosamine
, gonadotropins or polypeptide hormones, 8-Br-cAMP, theophylline or trifluoperazine (TFP). Radiolabeled proteoglycans were precipitated with 10% phosphotungstic acid. Maximum incorporation of isotope occurred in 45-60 min. Radiolabeled products were completely hydrolyzed with
chondroitinase
ABC. FSH, but not LH or hCG, yielded a significant log-dose response. High doses of hCG inhibited the ability of granulosa to respond to FSH. No other hormone altered the FSH dose-response curve. Addition of 8-Br-cAMP or theophylline mimicked the FSH response. The FSH effect was blocked by TFP, an inhibitor of calmodulin, but cAMP or theophylline overcame the effect of TEP. No distinct difference in response to these various compounds was noted between granulosa from small or large follicles. This system provides a biochemical marker for evaluating a mechanism of action for FSH.
...
PMID:Proteoglycan production by bovine granulosa cells in vitro occurs in response to fsh. 629 31
Retinas were labeled in culture with [3H]
glucosamine
or [3H]leucine and [35S]sulfate and extracted sequentially with physiologically balanced saline and 4 M guanidine HCl. They were dialyzed into associative conditions (0.5 M NaCl) and chromatographed on agarose columns. Under these conditions, some of the proteoglycans were associated in massive complexes that showed low buoyant densities when centrifuged in CsCl density gradients under dissociative conditions (4 M guanidine HCl). Much of the label in these complexes was in molecules other than proteoglycans. Most of the proteoglycans, however, were included on the agarose columns, where they appeared to be constitutionally of low buoyant density. They resisted attempts to separate potential low buoyant density contaminants from the major proteoglycans by direct CsCl density gradient centrifugation or by the fractionation of saline or 8 M urea extracts on diethylaminoethyl-Sephacel. The diethylaminoethyl-Sephacel fractions were either subjected to CsCl density gradient centrifugation or were chromatographed on Sephacryl S-300, in both cases before and after alkaline cleavage, to confirm the presence of typical O-linked glycosaminoglycans. The medium and balanced salt extracts were enriched in chondroitin sulfate and other sulfated macromolecules, possibly highly sulfated oligosaccharides, that resisted digestion by
chondroitinase
ABC but were electrophoretically less mobile than heparan sulfate. Guanidine HCl or urea extracts of the residues were mixtures of high and low density proteoglycans that were enriched in heparan sulfate.
...
PMID:Low buoyant density proteoglycans from saline and dissociative extracts of embryonic chicken retinas. 636 28
Rat ovarian granulosa cells were isolated from immature female rats after stimulation with pregnant mare's serum gonadotropin and maintained in culture. Proteoglycans were labeled with [35S]sulfate, [3H]
glucosamine
, [3H]serine, or [3H]mannose as precursors. A low buoyant density dermatan sulfate proteoglycan was separated from a larger hydrodynamic size, high buoyant density dermatan sulfate proteoglycan and from a heparan sulfate proteoglycan using DEAE-Sephacel and Sepharose CL-4B chromatography under dissociative conditions in the presence of detergent. This low buoyant density dermatan sulfate proteoglycan, which constituted approximately 30% of the 35S-labeled proteoglycans in the culture medium, has a relatively small hydrodynamic size (Kd = 0.45 on Sepharose CL-4B) and shows a broad buoyant density distribution in CsCl density gradients, primarily due to the heterogeneity in glycosaminoglycan composition. The average molecular weight of the protein coreoligosaccharide complex obtained by
chondroitinase
ABC digestion of the proteoglycan was estimated to be approximately 230,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After digestion with
chondroitinase
ABC, the dermatan sulfate chains (average Mr = 33,000) yielded 81% 4-sulfated disaccharides and 17% disulfated disaccharides (sulfate groups on the 6-position of the galNAc and probably on the 2-position of the iduronic acid). Alkaline borohydride treatment of this proteoglycan released three distinct size species of oligosaccharides; a species of N-linked oligosaccharide which contains mannose, glcNAc, and sialic acid, and two species of O-linked oligosaccharides. Trypsin digestion of the proteoglycan generated fragments which contain (a) glycosaminoglycan-peptides with an average of 2 dermatan sulfate chains, (b) clusters of O-linked oligosaccharide-peptides, and (c) N-linked oligosaccharide-peptides.
...
PMID:Characterization of low buoyant density dermatan sulfate proteoglycans synthesized by rat ovarian granulosa cells in culture. 641 57
We have shown previously that an activity which is capable of precipitating purified C1q and inhibiting some of the C1q-dependent biologic reactions could be solubilized from the membranes of both normal human peripheral B lymphocytes and a B cell-derived lymphoblastoid cell line (Raji), both of which are known to possess receptors for human C1q. In this report we present evidence that this membrane-associated C1q inhibitor is a
chondroitinase
-insensitive macromolecule and is the receptor for human C1q. The receptor was solubilized from membranes of Raji cells with Nonidet P-40 and purified to homogeneity using C1q-Sepharose 4B affinity chromatography. Equilibrium density gradient centrifugation analysis revealed that the complex could be resolved into a protein-rich, low density fraction and a carbohydrate-rich, high density fraction. The large hydrodynamic size, coupled with the high buoyant density, suggests that a proteoglycan is a constituent of the complex and indicates that the receptor might be a macromolecular complex of a proteoglycan portion noncovalently linked to a 60-70 kD glycoprotein. The glycoprotein moiety, in turn, consists of two or more identical (70,000 mol wt) polypeptide chains held together by disulfide bonds and constitutes the C1q receptor (C1qR). Sucrose density ultracentrifugation analysis showed that the isolated receptor sediments with an apparent rate of 4.2 S. Immunochemical analyses demonstrated that a typical preparation of the C1qR complex consists of approximately 23% uronic acid and approximately 21% galactosamine with a galactosamine-to-
glucosamine
ratio of 3.2. Binding of C1q to the receptor was found to be optimal at low ionic strength and neutral or near-neutral pH (7-7.4). The isolated receptor was found to inhibit C1q hemolytic function, abrogate C1q-dependent rosette formation, and block the C1q-dependent, cell-mediated cytotoxicity, all of which are activities mediated by the receptor.
...
PMID:Identification of the Raji cell membrane-derived C1q inhibitor as a receptor for human C1q. Purification and immunochemical characterization. 643 31
Acid mucopolysaccharides in the extracellular compartment of early chick blastoderms (16 h of incubation) were labelled with tritiated
glucosamine
and/or [35S]sulphate. The incorporation pattern was studied autoradiographically. Treatment with testicular hyaluronidase revealed a testicular hyaluronidase-sensitive fraction, mainly at the periphery of Middle Layer and Deep Layer cells, and a testicular hyaluronidase-resistant fraction, mainly at the ventral side of the Upper Layer. A biochemical analysis, utilizing
chondroitinase
ABC and nitrous acid, followed by cellulose acetate electrophoresis, demonstrated the synthesis of a non-sulphated fraction, i.e. hyaluronic acid and/or chondroitin, and a sulphated fraction, comprising two undersulphated components, i.e. chondroitin sulphate, and heparan sulphate or heparin. The appearance of different AMPS in specific areas of the early chick blastoderm is regarded as an early specialization of the extracellular compartment.
...
PMID:Localisation and characterization of acid mucopolysaccharides in the early chick blastoderm. 644 84
To elucidate precise chemical nature of urinary keratan sulfate (KS) of Morquio's disease, crude glycosaminoglycans (GAG) were separated from 24-hr urines of 3 patients with Morquio's disease and from pooled urine of a healthy boy, using cetylpyridinium chloride. KS fractions were then separated from the crude GAG after removal of other GAG and acidic glycopeptide by successive digestion with testicular hyaluronidase and
chondroitinase
ABC, and by nitrous acid treatment, followed by Dowex 1 column chromatography. The distribution of KS in several fractions (1.5 M Fr-5.0 M Fr) obtained by Dowex 1 column chromatography suggested polydispersity of urinary KS. The relative amounts (micrograms/24-hr urine/kg body weight) of the KS fractions excreted into Morquio's urine were 52-63 times as much as that excreted into normal urine. The KS fractions contained galactose,
glucosamine
and sulfate as the major constituents, together with fairly amounts of galactosamine and sialic acid, and small amounts of mannose, L-fucose and glucose. The KS fractions resembled sulfated glycopeptide with respect to the sugar composition. The contents of sulfate and sialic acid in each KS fraction from Morquio's urine were higher than those in the corresponding one from normal urine, whereas opposite was the case for the ratio of
glucosamine
to galactosamine. The sulfate contents in the KS fractions from Morquio's urine indicated that the patient excreted over-sulfated KS into urine. The chemical compositions of the KS fractions from Morquio's urine suggest that the sulfatase specific for 6-sulfate linked to sugars with the galactose configuration may act in a early step of the catabolism of oversulfated KS in the normal tissues.
...
PMID:Urinary keratan sulfate of Morquio's disease. 645 53
Polysaccharides and other complex carbohydrates were released by proteolysis of the chloroform-methanol insoluble residue of 10 day-old worms and eggs of Hymenolepis diminuta. Gas-liquid chromatographic analysis of alditol acetate derivatives of monosaccharides released from the polysaccharides by hydrolysis revealed that in the 10 day-old worm, glucose was the most abundant sugar, followed by galactose,
glucosamine
, galactosamine, fucose and possibly rhamnose. Mannose was least abundant and xylose was absent. In the egg, glucose and galactose were equally abundant, followed by the same sugars found in 10 day-old worms, and xylose was present. Uronic acid was detected in both fractions by specific chemical tests. None of the saccharide material from eggs and worms was susceptible to degradation by Streptomyces hyaluronidase, chondroitinase AC, and slightly susceptible to
chondroitinase
ABC, as shown by electrophoretic analysis on composite 2.2% acrylamide-agarose slab gels and 4.5/12.5% polyacrylamide gels before and after enzymatic treatment. One of the gel-separable bands, however, was degradable by both nitrous acid and Flavobacterium heparinase. Both bands from eggs were degradable by nitrous acid. These results suggest that eggs contain heparin and/or heparan sulfate and perhaps dermatan sulfate and that 10 day-old worms also have these polyglycans but possibly not chondroitin sulfate or hyaluronic acid.
...
PMID:Characterization of polysaccharides of the eggs and adults of Hymenolepis diminuta. 653 86
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.
...
PMID:Biosynthesis of glycosaminoglycans by epithelial and lymphocytic components of murine thymus. 660 Nov 42
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