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:4.2.2.7 (heparinase)
1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proteoglycans have been isolated from a high speed supernatant fraction of a mouse mastocytoma by procedures which should minimize alteration of the native protein-polysaccharide molecule. The methods used include in vivo labeling proteoglycans with 35S-sulfate, 3H-leucine and 3H-lysine, centrifugation of the tumor homogenate at 105,000 g, cetylpyridinium fractionation of the supernatant, and further purification of some of the fractions obtained by DEAE-cellulose column chromatography, gel filtration on Sepharose 4B and cellulose acetate electrophoresis. Two major sulfated proteoglycans were obtained, one containing keratan sulfate-like material (KSP-S), the other a heparin-like polymer (HP-S). The presence in HP-S of a compound similar to heparin was confirmed by its digestibility with flavobacterium heparinase. HP-S contained about 4 per cent protein. Glycine was the predominant amino acid, and serine did not appear to be involved in the peptide-carbohydrate linkage. The proteoglycan present in HP-S appeared to be homogeneous when examined using cellulose acetate electrophoresis. KSP-S was found to contain sialic acid and its protein content was significantly higher than that of HP-S. Glutamic and aspartic acids were the most abundant amino acids in KSP-S.
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PMID:Proteoglycans of soluble fraction of mouse mastocytoma. 12 69

A very high molecular weight mucin-like glycoprotein was isolated by gel filtration of interphotoreceptor matrix (IPM) from fresh bovine eyes and purified to apparent homogeneity by cesium chloride/guanidine hydrochloride (GuHCl) equilibrium density gradient centrifugation. Although a molecular weight in excess of 10(7) Da is suggested by gel filtration, the presence of SDS or GuHCl did not alter its elution position, indicating that the large size was not simply due to aggregation. Treatment of this material with disulfide reagents, however, led to a decrease in molecular size. On a relative basis, substantially more of this glycoprotein is present in IPM prepared from retina than from retinal pigment epithelium. While the carbohydrate and amino acid composition are not those of a true 'mucin', the large size and many other properties are quite 'mucin-like'. The carbohydrate composition suggests the presence of both N- and O-glycosidically linked sugar chains. The presence of a mucin-type O-glycosidic linkage is indicated by its susceptibility to alkaline cleavage, with concomitant loss of serine and threonine and increase in 240 nm absorbance; production of a fluorescent product upon reaction with cyanoacetamide; lectin binding properties; and production of N-acetylgalactosaminitol upon alkaline borohydride elimination. This glycoprotein was digested by pronase and trypsin, confirming its protein nature, but was resistant to digestion with chondroitin ABC lyase, hyaluronidase and heparinase, as well as RNAase, indicating that these components were not present to any appreciable extent. ELISA for cartilage keratan sulfate was also negative. Centrifugation in CsCl/GuHCl gradients indicated a density much lower than that of a proteoglycan or nucleic acid as well. In vitro biosynthetic studies suggest that both retina and retinal pigment epithelium may be major sources of material in the IPM. The elution patterns of radioactivity were strikingly similar to the UV elution patterns of IPM. The medium from retinal incubations contained very high molecular weight material which was resistant to enzymes which hydrolyse glycosaminoglycans, suggesting that retina may be the source of this high molecular weight, mucin-like glycoprotein.
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PMID:High molecular weight mucin-like glycoproteins of the bovine interphotoreceptor matrix. 154 29

The interaction of heparin (HP) with the cell-surface components of a human uterine epithelial carcinoma cell line (RL95) was studied. Binding of [3H]HP to cell surfaces was saturable in a dose- and time-dependent manner. HP and certain forms of heparan sulfate (HS) efficiently compete for [3H]HP binding. In contrast, other glycosaminoglycans, such as chondroitin sulfate, keratan sulfate, hyaluronic acid, and dermatan sulfate, do not compete for binding to these sites. Scatchard analysis revealed that [3H]HP bound to these sites with an apparent KD of 0.7-0.9 microM and a binding capacity of 9 x 10(6) sites/cell to attached cells. EDTA-detached cells displayed a similar apparent KD, but an approximately 2-fold increase in binding capacity. Protease digestion of cells on ice markedly reduced [3H]HP binding, indicating that these binding sites were associated with proteins. In contrast, heparinase treatment of cells stimulated binding by approximately 2-fold, indicating that a large fraction of these binding sites were occupied with endogenous ligand. We examined the structural features of HP/HS required for HP/HS binding. O-Sulfation, substitution of amino groups, and, to a lesser extent, the presence of carboxyl groups were important recognition features of HP/HS by cell-surface HP/HS-binding sites. N-Sulfation was not required. Photoaffinity labeling with 125I-sulfosuccinimidyl 2-(p-azidosalicylamido)-ethyl-1, 3-dithiopropionate-HP was used to identify HP/HS-binding proteins on RL95 cell surfaces. Proteins with M(r) values of 14,000-18,500 and 31,000 were photolabeled at the surfaces of attached cells. Photolabeling was blocked by the addition of excess HP, but not chondroitin sulfate. Additional proteins with M(r) values greater than 31,000 were photolabeled specifically on EDTA-detached cells. Moreover, the M(r) 14,000-18,500 and 31,000 proteins were retained on the EDTA-detached cells. These observations indicated that certain cell-surface HP/HS-binding proteins were not exposed when cells were attached to substrata. Proteins of similar M(r) values as the photolabeled components as well as many additional proteins were identified by heparin-agarose chromatographic selection of extracts of cells labeled metabolically with [35S]methionine or vectorially with Na125I at the cell surface. Fragments of cell-surface HP/HS-binding proteins were released from intact RL95 and mouse uterine epithelial cells by mild trypsinization and isolated by heparin-agarose affinity chromatography. Three peptides with M(r) values between 6000 and 14,000 required greater than 0.5 M salt for elution from heparin-agarose, retained HP binding activity in a 125I-HP gel overlay assay, and selectively bound [3H]HP in a solid-phase binding assay.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Identification of cell-surface heparin/heparan sulfate-binding proteins of a human uterine epithelial cell line (RL95). 160 62

Conditioned medium from Sertoli cells, prepared from testes of 20-day-old rats, contains component(s) that inhibit the incorporation of [3H]-thymidine into DNA of peritubular myoid cells (PMC) and inhibit the proliferation of PMC. These components are trypsin-resistant, heat-stable compounds having a molecular weight less than 30,000. The active inhibitory components in Sertoli cell conditioned medium are inactivated by treatment with heparinase, but not by treatment with hyaluronidase or chondroitin sulfate lyases. Addition of heparin or heparan sulfate results in inhibition of DNA synthesis by PMC in a dose-dependent manner, whereas other glycosaminoglycans (GAGs) examined (hyaluronic acid, keratan sulfate, and chondroitin sulfate) have no detectable effects. Heparin and heparan sulfate are unique among GAGs tested in inhibiting the characteristic multilayer growth pattern of PMC following the attainment of confluence in serum-rich medium. On the basis of these and other data presented, it is concluded that heparin and other heparin-like GAGs synthesized by Sertoli cells are implicated in the modulation of growth of PMC in vitro during co-culture. It is postulated that heparin may play a similar role in maintaining the quiescent peritubular myoid cell phenotype in vivo.
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PMID:Sertoli cells in culture secrete paracrine factor(s) that inhibit peritubular myoid cell proliferation: identification of heparinoids as likely candidates. 171 60

Glycosaminoglycans (GAGs) including chondroitin sulfate, dermatan sulfate, heparan sulfate, heparin, and keratan sulfate types I (corneal) and II (cartilage) added to buffer, plasma and urine were enzymatically depolymerized. Enzymes, including chondroitin ABC lyase (chondroitinase ABC), heparin lyase (heparinase), heparan sulfate lyase (heparitinase), endo-beta-galactosidase and keratanase were used to depolymerize each GAG. Depolymerized GAGs and GAG mixtures were fractionated using gradient polyacrylamide gel electrophoresis. Staining with alcian blue dye resulted in a distinctive and well resolved banding pattern for each GAG. When these same gels were silver stained, an increase in detection sensitivity of 1000-fold was obtained. Picogram quantities of an oligosaccharide standard in buffer could be detected with silver staining while nanogram quantities could be detected in urine or plasma. The banding pattern observed for each depolymerized GAG was well resolved from contaminants found in these biological fluids and from intact GAGs. Endogenous GAGs present in samples of human urine and plasma were first concentrated and then enzymatically depolymerized. Chondroitin or dermatan sulfates, heparan sulfate and keratan sulfate were each detected in both concentrated plasma and urine samples.
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PMID:Electrophoresis and detection of nanogram quantities of exogenous and endogenous glycosaminoglycans in biological fluids. 171 41

Follistatin, an activin-binding protein secreted by cultured rat granulosa cells, was shown to associate with the cell surface by affinity labeling with 125I-activin. Addition of follistatin to the cultured cells demonstrated a typical ligand-binding saturation curve, suggesting that granulosa cells have a specific binding site for follistatin. This binding was markedly inhibited by heparin and heparan sulfate, but not by chondroitin sulfates A and C, keratan sulfate, and dermatan sulfate. When granulosa cells were treated with glycosaminoglycan-degrading enzymes before or after addition of follistatin to the cultures, heparinase and heparitinase treatments resulted in significant suppression of the binding, whereas treatment with chondroitinase ABC had no effect. A competition study of the binding using heparin derivatives demonstrated that follistatin seemed to recognize O-sulfate groups in the heparin molecule. Heparitinase-treated granulosa cells exhibited almost full responsiveness to activin, indicating that the enzyme treatment had no effect on activin and receptor interaction. These results suggest that follistatin/activin-binding protein binds to heparan sulfate side chains of proteoglycans on the granulosa cell surface to regulate the various actions of activin.
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PMID:Follistatin, an activin-binding protein, associates with heparan sulfate chains of proteoglycans on follicular granulosa cells. 191 55

We have isolated a syngeneic monoclonal antibody (HepSS-1) reactive to a murine methylcholanthrene-induced fibrosarcoma, Meth-A. HepSS-1 also bound to a wide variety of established and fresh normal cells derived from not only mice but also other species such as human, monkey, rat, hamster, and chicken. Immunoprecipitation of surface iodinated Meth-A cell extract with HepSS-1, as well as Sepharose 4B gel chromatography of Meth-A cell extract and detection of antigens recognized by HepSS-1 by a sandwich-type radioimmunoassay revealed that the HepSS-1 antigens were composed of several molecular species, with one as large as approximately 10(6) daltons. The following evidence indicates that HepSS-1 specifically recognizes an epitope present in heparan sulfate glycosaminoglycan (HS-GAG). First, treatment of Meth-A cells with heparitinase or heparinase, but not with chondroitinase ABC or hyaluronidase, resulted in the loss of HepSS-1 binding. Second, HS-GAG but not seven other types of GAG (hyaluronic acid, heparin, chondroitin, chondroitin 4-sulfate, chondroitin 6-sulfate, dermatan sulfate, and keratan sulfate) inhibited HepSS-1 binding to Meth-A cells. Third, HepSS-1 bound with HS-GAG but not with the seven other types of GAG. From the binding analysis of HepSS-1 to various modified HS-GAG and whale omega-heparin, it is additionally suggested that HepSS-1 recognizes an epitope closely related to O-sulfated and N-acetylated glucosamine. We found that NIH 3T3 cells expressed more HepSS-1 epitopes at a low cell density than at confluency and in G2 + M than in G1, whereas NIH 3T3 cells transformed with Kirsten-ras oncogene or SV-40 expressed high levels of HepSS-1 epitopes and ceased to show the density-dependent change in the amount of HepSS-1 epitopes. These observations were also reproduced by using NIH 3T3 cells transformed with a temperature sensitive Kirsten murine sarcoma virus maintained at permissive and non-permissive temperatures. Thus HepSS-1 is a first monoclonal antibody to HS-GAG and seems to be useful to elucidate changes in cell surface HS-GAG in normal cell growth and cell transformation.
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PMID:A syngeneic monoclonal antibody to murine Meth-A sarcoma (HepSS-1) recognizes heparan sulfate glycosaminoglycan (HS-GAG): cell density and transformation dependent alteration in cell surface HS-GAG defined by HepSS-1. 243 Oct 47

Oligosaccharides prepared from glycosaminoglycans (GAGs) including heparin, heparan sulfate, chondroitin sulfates, dermatan sulfate, and keratan sulfate were analyzed using reverse-phase ion-pairing HPLC and ion-exchange HPLC with suppressed conductivity detection. The results were compared with those obtained by strong anion-exchange HPLC using uv detection. These oligosaccharides were first prepared by enzymatically depolymerizing the GAGs with enzymes including heparin lyase (EC 4.2.2.7), heparan sulfate lyase (EC 4.2.2.8), chondroitin ABC lyase (EC 4.2.2.4), and keratan sulfate hydrolase (EC 3.2.1.103). Analysis was then performed without derivitization under isocratic conditions with a limit of sensitivity in the picomole range. Preliminary studies suggest that this approach may be particularly useful in examining oligosaccharides having no uv chromophore such as those prepared from keratan sulfate.
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PMID:Analysis of glycosaminoglycan-derived oligosaccharides using reversed-phase ion-pairing and ion-exchange chromatography with suppressed conductivity detection. 251 May 51

Monoclonal antibodies, 17B1 and 17Q2, which are specific for large molecular weight mucous glycoproteins of airway epithelium, have been used to develop an ELISA method to quantitate the tracheal mucins of humans and rhesus monkeys. The assay is a double-sandwich system that does not depend on either the binding of mucous antigens to the microtiter plate or the use of a second antibody. The assay protocol includes (1) coating the microtiter well with purified IgG of 17B1 or 17Q2, (2) incubating the wells with mucous samples, (3) binding of alkaline phosphatase-conjugated IgG to the wells, and (4) developing the color with phosphate substrate. This ELISA method is very sensitive for human and rhesus monkey tracheal mucins. Quantitation is not affected by the presence of various proteoglycans (keratan sulfate, hyaluronate, heparin, heparan sulfate, and chondroitin sulfate). However, the quantitation is affected by the treatment of antigen with periodic acid and endo-beta-galactosidase. Other enzymes (e.g., neuraminidase, hyaluronidase, chondroitinase, heparitinase, heparinase, fucosidase, keratanase) have no effect on the antigenicity of substrate. The quantitation is linear, with a concentration from 0.2 to 4 ng protein/sample. The ELISA method developed in this study should be useful for quantitating the mucin content of various biologic fluids, such as sputum, bronchoalveolar lavage, and media from cultures following various pharmacologic and physiologic manipulations.
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PMID:An ELISA method for the quantitation of tracheal mucins from human and nonhuman primates. 262 58

Scatchard analysis of binding of 125I-basic fibroblast growth factor (FGF) to baby hamster kidney (BHK) cells revealed the presence of two binding sites: a high affinity site with KD of 20 pM and 80,000 sites per cell and a low affinity site with KD of about 2 nM and 600,000 sites per cell. The binding to the two sites could be separated by first washing the cells with 2 M NaCl at pH 7.5 which released the low affinity binding and then extracting the cells with 0.5% Triton X-100 to recover the 125I-basic FGF bound to high affinity sites. The binding to the high affinity site was acid sensitive, suggesting that it represented binding to the receptor. Binding to the low affinity site could be competed strongly by heparin and less strongly by heparan sulfate but not by chondroitin sulfate, dermatan sulfate, or keratan sulfate. Treatment of BHK cells with heparinase abolished 62% of the low affinity binding, suggesting that the low affinity binding represented binding to cell-associated, heparin-like molecules. A variety of other cell types, including bovine capillary endothelial (BCE) cells, also demonstrated both low and high affinity binding sites. To test whether the low affinity binding might play a role in the basic FGF stimulation of plasminogen activator (PA) production by BCE cells, heparin was added to BCE cultures at concentrations which totally blocked binding of 125I-basic FGF to the low affinity sites. Addition of the heparin did not diminish the increased PA production induced by basic FGF. This suggests that the low affinity binding has no direct role in the stimulation of PA production in BCE cells.
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PMID:High and low affinity binding sites for basic fibroblast growth factor on cultured cells: absence of a role for low affinity binding in the stimulation of plasminogen activator production by bovine capillary endothelial cells. 303 90


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