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)

Chondroitinase B and chondroitinase C were separated from an extract of Flavobacterium heparinum induced with chondroitin 6-sulfate by using column chromatography on hydroxylapatite. Chondroitinase C was eluted together with the activities of hyaluronidase, delta4,5glycosiduronase, and sulfatase. The latter two activities were eliminated exclusively by passing the crude chondroitinase C fraction through a phosphono-cellulose column pre-equilibrated with 0.07M sodium phosphate buffer (pH 6.8). Chondroitinase C was then purified by affinity chromatography using dermatan sulfate-bound AH-Sepharose 4B coated with the same glycosaminoglycan. Purification of the enzyme was achieved 18-fold and in 73% yield. On the other hand, the activities of delta4,5glycosiduronase and sulfatase were decreased to 50 and 60%, respectively, as compared with those in the crude chondroitinase B fraction, after passing the fraction through a column of phosphono-cellulose pre-equilibrated with 0.1M sodium phosphate buffer (pH 6.8). The remaining activities of these two enzymes were then eliminated from chondroitinase B by affinity chromatography with heparin-bound AH-Sepharose 4B coated with dermatan sulfate. In the affinity chromatography used in the present study, non-covalent coating of the glycosaminoglycan-bound (covalently) AH-Sepharose 4B with the same or another glycosaminoglycan was found to be important.
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PMID:Purification of chondroitinase B and chondroitinase C using glycosaminoglycan-bound AH-Sepharose 4B. 42 37

Soluble 125I-labeled type I collagen binds to cultured fibroblasts but not to cultured epithelia. The binding of the ligand to fibroblasts is reversible, saturable and highly specific for sequences contained within the helical portions of the alpha1 and alpha2 chains. The amount of ligand bound is dependent upon cell number and ligand concentration. Binding is decreased but measurable at 4 degrees C. The steady state binding is greater at 26 degrees than at 37 degrees C due to a more rapid dissociation of the ligand-acceptor complex at 37 degrees C. The half-life of the complex is 46 min at 37 degrees C and approximately 2.5 hr at 26 degrees C. Scatchard plots of binding data indicate a single class of high affinity binding sites (KD = 1.2 X 10(-11) M) with each fibroblast binding approximately 500,000 molecules at saturation. Pretreatment of fibroblasts with bacterial collagenase, chondroitinase ABC or testicular hyaluronidase does not affect the binding reaction, whereas pretreatment of the cells with phospholipase C increases the amount of ligand bound. Ligand binding is decreased but not abolished after fibroblasts are treated with trypsin concentrations which remove surface fibronectin. Fibroblast monolayers treated with antiserum against fibronectin bind the radiolabeled ligand normally. In contrast to collagen, addition of excess fibronectin does not accelerate the dissociation of bound ligand from fibroblasts. Possible functions for surface-bound collagen are discussed.
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PMID:Binding of soluble type I collagen molecules to the fibroblast plasma membrane. 45 36

This study demonstrates that the dorsal ectoderm of the stage 14 chick embryo synthesizes hyaluronic acid. About 49 to 52% of the H3 glucosamine-labeled glycosaminoglycan that is synthesized by explanted ectoderm can be identified as hyaluronic acid on the basis of its susceptibility to Streptomyces hyaluronidase or isolation of chondroitinase ABC digestion products. In addition, autoradiographic evidence shows that the ectoderm, unlike adjacent tissues like epithelial somites or neural tube, incorporates glucosamine into hyaluronidase-sensitive material which becomes largely extracellular and localized in the subectodermal cell-free space. Ultrastructural evidence shows that there is a fine fibrillar matrix between the ectodermal cells and in the subectodermal spaces when tannic acid is included in the primary fixative. This material resembles authentic hyaluronate, similarly fixed, and is absent when tannic acid is omitted from the fixative or when embryos have been previously treated in ovo with Streptomyces hyaluronidase. The concomitant reduction in the intercellular and subectodermal cell-free spaces after in ovo treatment with Streptomyces hyaluronidase supports the hypothesis that the dorsal ectoderm plays a morphogenetic role by contributing hyaluronate to the forming extracellular spaces. It is proposed that ectodermally derived hyaluronate might influence the morphogenesis of subjacent tissues such as the dermatome and neural crest.
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PMID:The synthesis of hyaluronic acid by ectoderm during early organogenesis in the chick embryo. 47 12

The parietal pleura of rabbits was incubated with 14C-glucosamine. It was found that 14C-glucosamine was incorporated into the fraction of crude glycosaminoglycans. Then the crude glycosaminoglycans were fractionated by using specific mucopolysaccharide-lyases (hyaluronidase from streptomyces hyalurolytics, chondroitinase AC and chondroitinase ABC). As a result, evidence was obtained that hyaluronic acid was synthesized in parietal pleura and was released into the surroundings.
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PMID:[Biosynthesis of hyaluronic acid in parietal pleura of the rabbit (author's transl)]. 49 96

Embryonic chick muscle contains two developmentally regulated lectins, which may be involved in cell interactions. These endogenous lectins are assayed as agglutinins of appropriate test erythrocytes. One of these, called lectin-2, interacts with specific glycosaminoglycans, especially heparin and dermatan sulfate. Lectin-2 is present at constant levels in both chick fibroblast and chick muscle cells throughout 14 days of culture but is released into the medium of cultured embryonic muscle after 7-8 days of culture, soon after myoblast fusion. Lectin-2 interacts strongly with a component of substrate-attached material in embryonic muscle cultures which is extractable from the cutlure dishes with alkali after the cells have been removed with ethylediaminetetraacetic acid. The active component in the substrate-attached material appears to be a glycosaminoglycan that is a more potent inhibitor of lectin-2 agglutination activity than any of the known glycosaminoglycans that we have tested. The active material is degraded by chondroitinase ABC but not by chondrotinase AC, hyaluronidase, or proteolytic enzymes and thus appears to be similar to dermatan sulfate. The results of these studies raise the possibility that lectin-2 functions by interacting with glycosaminoglycans, either associated with the cell surface or with the extracellular matrix.
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PMID:Extracellular lectin and its glycosaminoglycan inhibitor in chick muscle cultures. 52 83

The development of the sclerotome is considered as a model for the formation of mesenchyme from an epithelium. In early epithelial somites, transmission and scanning electron microscopy indicate considerable ultrastructural similarity between the future sclerotome and dermamyotomal regions. Subsequently, these two regions diverge in their development. In the forming dermamyotome, junctional complexes become more extensive and the cells become elongated, closely applied to each other, and have angular surface contours. In the forming sclerotome, there is an early reduction in apical junctions. The cells elongate, keeping their original polarity, and acquire numerous filopodia which contain punctate junctions at sites of cell-to-cell contact. Associated with cellular extension is an expansion of the intercellular spaces which do not contain any ultrastructurally recognizable material. Evidence for a role of hyaluronic acid in the expansion of the intercellular spaces is presented. As identified by the susceptibility of cetylpyridinium chloride precipitates to Streptomyces hyaluronidase and chromatographic separation of chondroitinase ABC digestion products, as much as 64--68% of the [3H]glucosamine-labeled glycosaminoglycans synthesized by explanted somites is hyaluronic acid. In addition, hyaluronidase-sensitive label is localized in the intercellular spaces of the sclerotome, as demonstrated by autoradiography. When Streptomyces hyaluronidase is injected in ovo into living embryos, the sclerotomal mesenchyme differentiates morphologically, but intercellular spaces are drastically reduced. It is hypothesized that the sclerotomal cells produce a hyaluronate-enriched extracellular matrix which is inflated by hydration to mediate the expansion of the sclerotomal mass towards the notochord.
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PMID:The role of extracellular matrix in the formation of the sclerotome. 52 73

Disc material from horse, ox, sheep, pig, dog and cat was stained by the Alcian-blue-critical electrolyte concentration technique and with the standard and two-step periodic acid Schiff methods. The effects of pretreatment with hyaluronidase and with chondroitinase was also evaluated. There appears to be a small increase in total cellular glycosaminoglycan content with age in all species: cellular material of high molecular weight however only increases in aged animals. The degree of sulphation of cellular glycosaminoglycans does not vary with age or with position in the disc.
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PMID:Staining of glycosaminoglycans in intervertebral disc cells. 60 1

The acidic glycosaminoglycans (AGAG) in normal portions of human gastric tissue were separated by electrophoresis in 3 buffer systems. Paper chromatographic separation of the constitutional disaccharide units by digestion of chondroitin sulfates (CS) with chondroitinase-ABC and chondroitinase-AC was carried out after fractionation of CS by ion-exchange resin column chromatography. Thin-layer chromatography of hexosamines and other biochemical analysis were also performed. The presence of hyaluronic acid in the gastric tissue was substantiated by the enzymatic susceptibility to streptomyces hyaluronidase. The results indicated that human gastric AGAG consisted of, in the order of amount, heparan sulfates, dermatan sulfate, hyaluronic acid, chondroitin-4-sulfate, chondroitin-6-sulfate and presumably oversulfated chondroitin sulfate.
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PMID:A study of acidic glycosaminoglycans in human gastric tissue. 61 34

Acidic glycoconjugates (glycosaminoglycans and glycoprotein) were obtained, from myometrium of ovariectomized rabbit under estrogenic condition, by pronase digestion, fractionation with cetylpyridinium chloride and Dowex I column chromatography, in succession. Composition of acidic glycoconjugates was determined enzymatically, employing Streptomyces hyaluronidase, chondroitinase AC II, chondroitinase ABC and crude heparinase. Each glycoconjugate was distributed in 3 approximately 8 fractions obtained by Dowex I column chromatography, indicating its charge and/or molecular heterogeneity. Acidic glycoconjugates consisted of hyaluronic acid (13.4%), chondroitin sulfates A plus C (39.4%), dermatan sulfate (24.6%), heparan sulfate (18.7%) and acidic glycoprotein (most probably sialoglycoprotein) (3.9%). Composition of acidic glycoconjugates in myometrium differed remarkably from that in whole uterus. Myometrium was abundant in chondroitin sulfate isomers (chondroitin sulfates A plus C plus dermatan sulfate), but lacked sulfated glycoprotein. The present results suggested that myometrium and endometrium of uterus may play quite different roles in reproduction.
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PMID:Composition of acidic glycoconjugates (glycosaminoglycans and glycoprotein) in myometrium of rabbit uterus under estrogenic condition. 71 60

The chorionic villi of placentas, 10 to 40 weeks of gestation, were examined for A and B blood group antigens with an immunoferritin technique. No specific ferritin attachment was shown on the plasma membrane of the villous trophoblasts. Furthermore, after trophoblast cell-surface mucosubstances (perhaps the barrier of the placental antigenicity, according to some authors) were digested with several enzymes, such as neuraminidase, hyaluronidase, chondroitinase ABC, pepsin, trypsin, and pronase, no ferritin tagging was observed on the plasma membrane of the villous trophoblasts. We have concluded that our failure to detect the A and B blood group antigens was not due to the masking of antigens by mucosubstance coating the trophoblasts, but was due to the intrinsic deficit of those antigens in the plasma membrane of the human trophoblasts.
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PMID:Innumoelectron microscopy of the human chorionic villus in search of blood group A and B antigens. 79 65


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