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)

We have developed a monoclonal antibody AF-28 that specifically recognizes a neo-epitope on polypeptides with N-terminal FFGVG ... sequences. This sequence is found at the N-terminus of aggrecan fragments that have been digested with matrix metalloproteinases (MMPs). By immunoblotting, monoclonal antibody AF-28 specifically detected G2 fragments derived from an aggrecan G1-G2 substrate digested with stromelysin, collagenase, gelatinase and matrilysin, but failed to detect G2 fragments obtained from elastase, trypsin or cathepsin B digests. Undigested G1-G2 was not detected. In addition, AF-28 antibody detected fragments derived from whole aggrecan and this detection did not require prior treatment with chondroitinase or keratanase. Competition experiments confirmed that peptides containing internal ... FFGVG ... sequences were not detected by the antibody, while native MMP-digested aggrecan fragments and a synthetic 32-mer peptide with FFGVG ... N-termini were equally competitive on a molar basis. An FFGVG 5-mer, and an FGVGGEEDI9-mer which lacked the N-terminal phenylalanine residue, were 50 times and 230 times respectively less competitive than the FFGVG ... 32-mer. Two fragments from the interglobular domain, F342-F373 and F342-D441, that are predicted products of G1-G2 digestion by neutrophil collagenase but have not previously been detected, could be detected with AF-28. The epitope recognized by AF-28 was also detected in human synovial fluids by Western blot analysis. A broad band of 100-200 kDa was detected in some patients and a dominant band of 40-60 kDa was found in two patients. The size of this small fragment corresponds with that seen for the porcine F342-E373 product and may represent the natural physiological product of aggrecan cleaved in vivo at both the MMP site (... DIPEN341 decreases F342FGVG ...) and the aggrecanase site (... ITEGE373 decreases A374RGSVI ...).
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PMID:Development of a cleavage-site-specific monoclonal antibody for detecting metalloproteinase-derived aggrecan fragments: detection of fragments in human synovial fluids. 754 17

Exposure to AG73, a synthetic peptide (LQVQLSIR) from the COOH-terminal region of the laminin alpha1 chain, induces a malignant phenotype in B16F10 melanoma cells. Coinjection of this peptide with the cells results in an increase of lung tumors and also the formation of liver tumors in approximately 50% of the mice (W. H. Kim et al., Int. J. Cancer, 77: 632-639, 1998). Here we have characterized the cell surface receptor and its functional groups on B16F10 cells. Peptide affinity chromatography identified a cell surface protein eluting with 1 M NaCl, which ran in SDS gels as a broad band of M(r) approximately 150,000-200,000. Digestion with heparitinase and chondroitinase produced a core protein of lower molecular weight (M(r) approximately 90,000). Involvement of the glycosaminoglycan (GAG) side chains was demonstrated by inhibition of cell binding to the peptide by heparin, heparan sulfate, and chondroitin sulfate B, but not by chondroitin sulfates A or C, or hyaluronic acid. The IC(50) for heparin was the lowest, followed by heparan sulfate, then chondroitin sulfate B, suggesting that the overall sulfation of the GAG side chain is critical. This was confirmed by inhibition of attachment with chemically modified heparin and heparan sulfate, which also showed that N or O linkages were not important for function. Using sized heparin fragments to inhibit cell binding to the peptide demonstrated that 16-mer is the minimum length required. B16F10 cells form a network when grown on Matrigel, and this is prevented by addition of the AG73 peptide. The GAGs alone did not affect network formation, but heparin, heparan sulfate, and chondroitin sulfate B reversed the inhibitory effect of the peptide, whereas other GAGs were inactive. Furthermore, removal of cell surface GAGs inhibited cell attachment to the peptide. Cells treated with glycosidases and coinjected with the peptide formed liver tumors equal to the control group receiving no peptide, suggesting that the GAGs play an early role in peptide-mediated tumor metastasis. These data indicate that the B16F10 cell receptor for a laminin metastasis-promoting sequence is a heparan sulfate/chondroitin sulfate-containing proteoglycan, and these GAG side chains are functionally important in the cell-peptide interaction.
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PMID:The B16F10 cell receptor for a metastasis-promoting site on laminin-1 is a heparan sulfate/chondroitin sulfate-containing proteoglycan. 1206 3

Pleiotrophin is an 18-kDa heparin-binding growth factor, which uses chondroitin sulfate (CS) proteoglycan, PTPzeta as a receptor. It has been suggested that the D-type structure (GlcA(2S)beta1-3GalNAc(6S)) in CS contributes to the high affinity binding between PTPzeta and pleiotrophin. Here, we analyzed the interaction of shark cartilage CS-D with pleiotrophin using a surface plasmon resonance biosensor to reveal the importance of D-type structure. CS-D was partially digested with chondroitinase ABC, and fractionated using a Superdex 75pg column. The > or =18-mer CS fractions showed significant binding to pleiotrophin, and the longer fractions had stronger affinity for pleiotrophin than the shorter ones. The approximately 46-mer CS fraction bound to densely immobilized pleiotrophin with high affinity (K(D) = approximately 30 nM), and the binding reactions fitted the bivalent analyte model. However, when the density of the immobilized pleiotrophin was lowered, the strength of affinity remarkably decreased (K(D) = approximately 2.5 microM), and the reactions no longer fitted the model and were considered to be monovalent binding. The 20 approximately 24-mer fractions showed low affinity binding to densely immobilized pleiotrophin (K(D) = 3 approximately 20 microM), which seemed to be monovalent. When approximately 22-mer CS oligosaccharides were fractionated by strong anion exchange HPLC, each fraction differed in affinity for pleiotrophin (K(D) = 0.36 approximately >10 microM), and the affinity correlated with the amounts of D- and E- (GlcAbeta1-3GalNAc(4S,6S)) type oversulfated structures. These results suggest that the binding of pleiotrophin to CS is regulated by multivalency with CS approximately 20 mer as a unit and by the amounts of oversulfated structures.
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PMID:The binding of chondroitin sulfate to pleiotrophin/heparin-binding growth-associated molecule is regulated by chain length and oversulfated structures. 1637 46

Glycosaminoglycans from the body of marine clam Scapharca inaequivalvis were extracted at about 0.15- 0.18 mg/g of dry tissue, composed of dermatan sulfate (DS) (approx. 74%) and heparan sulfate (26%). After treatment with nitrous acid, DS was isolated for further complete structural characterization. Agarose-gel electrophoresis in combination with various enzymes, chondroitin ABC lyase, chondroitin B lyase, chondroitin ACII lyase from Arthrobacter aurescens, and chondroitin AC lyase from Flavobacterium heparinum, confirmed the DS nature of this polysaccharide. Furthermore, by evaluating the unsaturated disaccharides produced by the action of the various lyases, this natural polymer was found to be composed of approx. 75% of disaccharides containing iduronic acid (IdoA) mainly found in disaccharides monosulfated in position 4 of N-acetylgalactosamine (GalNAc) and disulfated in position 2 of the IdoA and 4 of GalNAc (disaccharide B typical of DS). In contrast, glucuronic acid was found to be mainly associated with the nonsulfated disaccharide (approx. 92%), while the rest formed low percentages of monosulfated disaccharides in position 4 or 6 of GalNAc preferentially located inside the chains. Generally, this GAG possesses a peculiar structure, due to the presence of significant amounts of nonsulfated disaccharide mainly located close to the nonreducing end, to the elevated percentage of the disaccharide B, and to the presence of not previously reported low amounts of the disaccharide monosulfated in position 2 of the uronic acid. S. inaequivalvis DS was also found to have a mean molecular mass of approx. 27,000 Da and a mean charge density of 1.10 that increases to 1.54 for the carbohydrate backbone composed of IdoA residues. (1)H-NMR and (13)C-NMR analyses confirmed the nature of S. inaequivalvis polymer revealed by the presence of signals related to DS corresponding to the residue of IdoA and GalNAc mainly sulfated at the C4 along with the presence of a signal belonging to the residue of H1 IdoA-2SO(4). S. inaequivalvis DS was further depolymerized by partial controlled digestion with chondroitinase ABC and separated into oligosaccharides by online HPLC/ESI-MS to obtain sequence information. The most prominent generated oligosaccharides comprised the repeating unit Delta Hex-GalNAcSO(4) thus confirming the results obtained by disaccharide analysis and the structures of the major oligosaccharides (from 6- to 10-mer) confirmed, by means of the LC-MS, the presence of approx. 20% of nonsulfated disaccharide. Furthermore, a minor but significant percentage of a monosaccharide having an m/z 300 and corresponding to GalNAcSO(4) belonging to the DS nonreducing end was observed along with saturated hexasaccharide derived from the nonreducing terminus of the intact DS ending with a uronic acid residue. Finally, S. inaequivalvis DS was calculated to possess a high heparin cofactor II activity of 169.2 +/- 10.7% fairly similar to that of several DS samples purified from porcine and bovine tissues.
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PMID:Structural characterization and antithrombin activity of dermatan sulfate purified from marine clam Scapharca inaequivalvis. 1905 86