Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.12 (chondroitinase)
 2,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monomer proteoglycan was isolated from porcine ovarian follicular fluid by isopycnic CsCl centrifugation in the presence of 4 M guanidine HCl and protease inhibitors. The elution profile of the D1 preparation on Sepharose 2B was similar to that of monomer proteoglycan from bovine nasal cartilage, indicating a similar molecular size. Follicular fluid proteoglycans consist of about 20% protein, 50% dermatan sulfate, and 20% oligosaccharides rich in sialic acid, galactose, mannose, glucosamine, and galactosamine. The amino acid composition of this proteoglycan is significantly different from that of cartilage proteoglycans, with a higher proportion of aspartic acid, threonine, and lysine, and lower amounts of proline and glycine. Alkali-released dermatan sulfate chains are larger on Sepharose 6B (average Mr = 56,000) than chondroitin sulfate chains from cartilage proteoglycans (average Mr = 25,000), and iduronic acid accounts for 9% of total hexuronic acid. Disaccharide units released by chondroitinase ABC consists of 67% 4-sulfated, 22% 6-sulfated, 5% non-sulfated, and 5% disulfated disaccharides. After treatment with 0.05 M NaOH, 1 M NaBH4 at 45 degrees C for 24 h, two major sialic acid-containing oligosaccharides were observed on Sephadex G-25, corresponding to penta- and hexasaccharides. The pentasaccharide contained sialic acid, galactose, glucosamine, and galactosamine in the proportions 1:2:1:1. The galactosamine is O-glycosidically linked to the protein core. This oligosaccharide accounts for approximately 77% of all the sialic acid in the follicular fluid proteoglycans. The hexasaccharide fraction contained sialic acid, galactose, mannose, and glucosamine in the proportions 1:2:1:2. It also contained a small amount of fucose and galactosamine. The linkage of these oligosaccharides to the protein core remains to be determined. The follicular fluid proteoglycans, unlike those from cartilage, do not interact with hyaluronic acid. Digestion with trypsin, chymotrypsin, or plasmin released dermatan sulfate-peptides nearly as small as those released by papain or alkali; in contrast, cartilage proteoglycans were resistant to plasmin and released peptides containing an average of more than four chondroitin sulfate chains after trypsin or chymotrypsin digestion.
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PMID:Isolation and characterization of proteoglycans from porcine ovarian follicular fluid. 76

Eosinophil migration toward a concentration gradient of a chemotactic factor is regulated at four levels. Diverse immunologic pathways generate stimuli with eosinophil chemotactic activity, including the complement products C5a and a fragment of C3a and the peptide products of mast cells and basophils activated by IgE-mediated reactions, such as eosinophil chemotactic factor of anaphylaxis (ECF-A) and other oligopeptides. The intrinsic preferential leukocyte activity of the chemotactic stimuli represents the second level of modulation, with ECF-A and other mast cell-derived peptides exhibiting the most selective action on eosinophils. The third level of control of eosinophil chemotaxis is composed of inactivators and inhibitors of chemotactic stimuli and is exemplified by degradation of C5a by anaphylatoxin inactivator or chemotactic factor inactivator and of ECF-A by carboxypeptidase-A or aminopeptidases. The activity of ECF-A is uniquely suppressed by equimolar quantities of its NH2- terminal tripeptide substituent, presumably by eosinophil membrane receptor competition. Factors comprising the fourth level of regulation, which alter eosinophil responsiveness to chemotactic stimuli, include the chemotactic factors themselves, through deactivation; nonchemotactic inhibitors such as the COOH-terminal tripeptide substituent of ECF-A, the neutrophil-immobilizing factor (NIF), the phagocytosis-enhancing factor Thr-Lys-Pro-Arg, and histamine at concentrations greater than 400 ng/ml; and nonchemotactic enhancing principles represented by ascorbate and by histamine at concentrations of 30 ng/ml or less. Local concentrations of eosinophils called to and immobilized at the site of a hypersenitivity reaction may express their regulatory functions by degrading the chemical mediators elaborated including histamine, slow-reacting substance of anaphylaxis (SRS-A), and platelet-activating factor (PAF) by way of their content of histaminase, arylsulfatase B, and phospholipase D, respectively. Immunologic pathways may thus provide the capability for early and specific host defense reactions with a later influx of eosinophils preventing irreversible local tissue alterations or distant organ effects.
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PMID:Modulation of human eosinophil polymorphonuclear leukocyte migration and function. 79 10

Since the 1960s, the loss of sulfomucin from colonic epithelium has been considered to be an indicator of an early stage of carcinogenesis; yet, the biochemical basis for this phenomenon has never been elucidated. We recently prepared a monoclonal antibody (mAb) 91.9H that immunoprecipitates the normal colonic mucins metabolically incorporating [35S]-sulfate. This mouse IgG1 antibody did not cross-react with colon carcinoma mucins that lack sulfate groups. Using normal colonic epithelia unlabeled or radiolabeled with [35S]sulfate and [3H]glucosamine, we purified a high molecular weight glycoprotein that reacts with mAb 91.9H. This was achieved by a combination of DEAE-cellulose anion-exchange chromatography, consecutive treatments with chondroitinase ABC plus heparitinase and with sodium dodecyl sulfate plus 2-mercaptoethanol, and gel filtration on Sepharose CL-2B in the presence of 8 M urea. Antibody reactivity was found in acidic but not neutral high molecular weight glycoproteins. After Sepharose CL-2B fractionation, the mAb 91.9H-reactive fractions consisted of a component with an approximate molecular weight of 500,000-900,000. A purified sulfomucin contained protein, neutral sugar, amino sugar, sialic acid, and sulfate in an approximate ratio of 2.5:1.0:1.1:0.4:0.5. The polypeptide portion was rich in hydrophilic amino acids, particularly threonine. Binding of mAb 91.9H in solid-phase assays was inhibited to 50% by purified normal colon acidic mucin at doses of 5-50 micrograms/ml, depending on different preparations. Various glycosaminoglycans or sulfatides did not show inhibitory activity. Sulfomucin reactivity with mAb 91.9H, as determined by solid-phase-binding inhibition and by dot blot assays, was significantly reduced by chemical desulfation of sulfomucins with anhydrous hydrochloric acid, suggesting that sulfate groups served as a portion of the immunochemical determinant for this antibody. Sulfate residues were apparently linked to alkaline-sensitive carbohydrate chains, but alkaline-released carbohydrate chains did not react with mAb 91.9H. Immunohistochemical examinations showed that mAb 91.9H bound normal colonic epithelial cells, which also stained with high-iron diamine, more strongly than it bound colon carcinoma cells.
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PMID:Human colonic sulfomucin identified by a specific monoclonal antibody. 191 91

A 22 x 10(3) Mr protein (abbreviated 22K) that copurifies with dermatan sulfate proteoglycans (DS-PGs) following the biochemical fractionation of bovine fetal skin has been evaluated for adhesion-promoting activity in vitro using Balb/c 3T3 cells, as well as bovine and human dermal fibroblasts. Substrata coated with 22K protein promote attachment of a subset of 3T3 and dermal fibroblasts that respond to plasma fibronectin (pFN) substrata. Cells on 22K protein display partial cytoplasmic spreading, comparable to that of cells adhering to cell-binding fragments of pFN. Adhesion activity of 22K is not due to contamination with known adhesive proteins of dermal matrices and is not dermal cell type-specific, since two classes of neuronal cells also respond effectively to 22K substrata. DS-PGs from cartilage or skin completely inhibit 22K adhesion activity when the PGs are adsorbed to 22K substrata under conditions prohibiting PGs from binding to substrata directly. Cartilage chondroitin/keratan sulfate proteoglycan at much higher concentrations is only partially inhibitory. Inhibition by DS-PGs is mediated by DS chains binding to 22K. Properties of the cell surface 'receptor' for 22K protein were tested by several approaches. It is not cell surface DS-PG, since: (1) cells unable to produce this proteoglycan class also responded; (2) cells treated with chondroitinase ABC responded equally well; and (3) substrata of proteoglycan-binding platelet factor-4 generated responses from cells that were quantitatively and qualitatively different. A synthetic peptide in the medium containing the Arg-Gly-Asp-Ser (RGDS) sequence completely inhibited responses to 22K substrata. This observation, coupled with sequencing data of 22K protein revealing an Arg-Gly-Ala-Thr sequence at residues 151-154, suggest that 22K protein mediates adhesion by cell surface integrin binding. Therefore, this newly discovered matrix protein from skin may serve as a communication link between the dermal fibroblast cell surface and its extracellular matrix environment.
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PMID:Extracellular matrix adhesion-promoting activities of a dermatan sulfate proteoglycan-associated protein (22K) from bovine fetal skin. 193 76

Previous studies from this laboratory have demonstrated that arylsulfatase B (ASB) is phosphorylated by a protein kinase, which is the first finding of phosphorylation in lysosomal hydrolases. The present study was undertaken to characterize the sites of phosphorylation in ASB from transplanted human lung cancer and from normal human tissues, and to identify type of tumor protein kinase responsible for the phosphorylation of ASB. When ASB purified from liver and placenta was phosphorylated in vitro by a cAMP-dependent protein kinase, it gave a single tryptic phosphopeptide (X) and phosphothreonine. On the other hand, the tumor ASB which had been phosphorylated in vivo demonstrated two phosphopeptides X and Y. Since the tumor ASB had been shown to be phosphorylated both at threonine and serine residues, phosphorylation at threonine residue of peptide X, which is phosphorylated by a cAMP-dependent protein kinase, will be cancer-associated. Through photoaffinity labeling with a labeled cAMP analogue to detect regulatory subunits of cAMP-dependent protein kinase subtypes, it was found that the cAMP-dependent protein kinase in the transplanted lung tumor was largely type II which can be ascribed to the appearance of highly phosphorylated ASB in the tumor.
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PMID:Protein phosphorylation of human lysosomal arylsulfatase B from normal and cancer tissues. 338 98

An acidic variant form of arylsulfatase B from normal leukocytes and chronic myelogenous leukemia (CML) leukocytes was found to be phosphorylated at its serine and threonine residues through in vivo phosphorylation with 32Pi. However, the predominant phosphorylation site was serine in normal cells, in contrast to threonine in CML cells. A cyclic AMP-dependent protein kinase was responsible for phosphorylation of the sulfatase of CML cells.
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PMID:Protein phosphorylation of lysosomal arylsulfatase B in normal and leukemic leukocytes. 346 94

Many lysosomal hydrolases in cases of human cancer were found to be accompanied by acidic variant forms together with the major hydrolase components. Such variants were found to be phosphorylated not only at their carbohydrate moiety which contributes largely to their acidic property, but also at the protein moiety. We identified a cAMP-dependent protein kinase which is responsible for phosphorylation of arylsulfatase B. The protein kinase activity toward the sulfatase was considerably higher in transplanted lung cancer than in normal lung in the presence of cAMP. The B enzyme purified from normal human liver was found to contain 0.6mol of Pi/mol of B enzyme, and protein kinase treatment added a further 1.3mol Pi to give a single phosphopeptide (X) containing phosphothreonine. On the other hand, the B1 enzyme purified from transplanted human lung cancer which had been labeled in vivo with [32P] Pi revealed at least two phosphopeptides (X and Y). Assuming that the sulfatase from liver and lung cancer possesses the same number of available phosphorylation sites, phosphorylation of site X (Thr) which is available only by deliberate phosphorylation of the native, ordinary B enzyme, appears to be cancer-associated. Increased phosphorylation of the sulfatase resulted in a maximum 50% elevation in arylsulfatase activity, followed by a decrease in the activity upon overphosphorylation, using an artificial substrate.
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PMID:[Phosphorylation of lysosomal hydrolases in human cancer and its significance]. 360 35

Human lung cancer transplanted into athymic mice contains predominantly an acidic variant (designated B1) of lysosomal arylsulfatase B. B1 enzyme was suggested to be phosphorylated and sialylated (Gasa, S., Makita, A., Kameya, T., Kodama, T., Koide, T., Tsumuraya, M., and Komai, T. (1981) Eur. J. Biochem. 116, 497-503). In order to determine the localization of phosphate in B1 enzyme, we labeled in vivo the transplanted tumor with [32P]H3PO4 or [3H]glucosamine and purified B1 enzyme by immunoprecipitation. Bio-Gel chromatography of the labeled B1 enzyme treated with endoglycosidase H demonstrated that both the excluded and included materials were labeled with 32P and 3H. From acid hydrolysate of the excluded materials, phosphorylated serine and threonine were detected. Protein phosphorylation of arylsulfatase was confirmed by in vitro labeling experiments with [gamma-32P]ATP. By incubation of the tumor homogenate with ATP followed by isolation of the enzymes, B1 enzyme had a significant amount of radioactivity, whereas the B enzyme had little; by exogenous protein kinase, partially purified B enzyme was phosphorylated 35 times more than B1 enzyme. Acid hydrolysate of the included materials in the Bio-Gel column demonstrated mannose 6-phosphate and an unknown phosphorylated compound which migrates more than Man-6-P on electrophoresis and chromatography.
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PMID:Phosphorylation on protein and carbohydrate moieties of a lysosomal arylsulfatase B variant in human lung cancer transplanted into athymic mice. 640 42

A glycopeptide fraction containing glucuronic acid as a component sugar was extracted and purified from squid cartilage to give a single band migrating much slower than hyaluronic acid in cellulose acetate electrophoresis. The molecular weight of the glycopeptide was fairly large since its Kav value in Sephadex G-200 chromatography was 0.18; however, it was soluble in 66% ethanol. This glycopeptide contained glucuronic acid, glucosamine, galactosamine, galactose, and fucose. The total amino acid content was 1.87 mumol of amino acid per mg of the glycopeptide. Threonine, serine and proline represented 80% of the amino acids. Digestion with chondroitinase ABC or reaction with nitrous acid did not result in degradation of the glycopeptide; however, it was completely degraded by reaction with 0.5 M KOH at 37 degrees C. Two hexasaccharides were separated from the alkaline degradation products, and they both contained glucuronic acid, fucose, galactosamine, and reducing terminal glucosamine in the molar ratio, 2:1:2:1. These results indicated that the glycopeptide contains glucuronic acid-containing sugar chains that are distinct from any known glycosaminoglycan.
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PMID:Glucuronic acid-containing glycopeptide from squid cartilage. 662 77

A 29-kDa monomeric dispase-digestive fragment of human plasma fibronectin has been purified by heparin affinity chromatography. The NH2-terminal sequence was determined as Ala1687-Val-Thr-Thr-Ile-Pro-Ala-Pro. By mass spectrometry the molecular weight was determined to be 30,241.9 with standard deviation of 3.9 amu. Therefore, we defined the C-terminal sequence of the 29-kDa fragment as Arg1957-Lys-Lys-Thr-Gly-Gln-Glu. This indicates that the fragment is composed of 277 amino acids. 125I-fibronectin and the 125I-labeled 29-kDa fragment bound to HL-60 (human acute promyelocytic leukemia) cells in a time-dependent, saturable, and reversible manner. Approximately 120 min was required to reach maximal binding. There were no differences in quantity or rate of binding of labeled fibronectin and 29-kDa fragment at temperatures of 4 degrees, 22 degrees, and 37 degrees C. The number of binding sites per HL-60 cell of fibronectin and the 29-kDa fragment were 140,000 with a Kd of 133 nM and 108,000 with a Kd of 250 nM, respectively. The binding of fibronectin to HL-60 cells was completely inhibited by this fragment, and by the peptides of RGDS and CS1 with IC50s of 3.6, 840, and 670 microM, respectively. Native fibronectin inhibited the direct binding of the 29-kDa fragment to HL-60 cells; however, RGDS peptide, peptide CS1, or two melanoma cell adhesion-promoting domain peptides in this 29-kDa fragment (peptide I; Tyr1906-Val1924, peptide II; Asp1946-Thr1960) did not block this binding. Neither heparitinase nor chondroitinase treatment of cells had any effect on these bindings. These results indicate that the C-terminal cell- and heparin-binding domain of fibronectin mediates HL-60 cell binding by direct interaction independently of RGD, CS1, and melanoma cell adhesion domains in this fragment.
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PMID:Binding site in human plasma fibronectin to HL-60 cells localizes in the C-terminal heparin-binding region independently of RGD and CS1. 769 49


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