Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Some proteases, i.e. trypsin, alpha-chymotrypsin, thermolysin, proteinase K, alpha-amylase, collagenase, and papain were investigated on their effect on isolated zonular fibers. All these enzymes but collagenase were zonulolytic active. An attack on the ground substance of the fibers by substances solving glycosaminoglycans and proteoglycans (hyaluronidase, EDTA, guanidinium chloride, H2O2) showed an increased effect of the enzymes used. These results suggest that the interfibrillar matrix has a protective function on the zonular fibers.
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PMID:[The attack of different proteases on isolated zonular fibers (author's transl)]. 13 75

The chemical nature of anionic sites located on both fronts of the endothelial cells (ECs) and in the basement membrane (BM) of mouse brain capillaries was studied using tissue sections embedded in Lowicryl K4M and cationic colloidal gold. Before labelling with cationic probe, the sections were digested with the following enzymes: trypsin, papain, pronase E, proteinase K, collagenase, chondroitinase ABC, hyaluronidase, heparinase, heparitinase, neuraminidase and endoglycosidase H. The results indicate that the negatively charged surface layer on the luminal front differs in chemical nature from that on the abluminal front of the EC. Anionic sites located on the luminal surface of the plasmalemma of the ECs are mainly contributed by sialic acid residues of acidic glycoproteins. On the contrary, the anionic domains on the abluminal front of the EC represent mixed proteoglycan and acid glycopeptides containing hydrophobic amino acids, sialic acid residues, and are rich in heparan sulphate-bearing glycosaminoglycans. The anionic sites of the BM are contributed in a substantial degree by chondroitin and heparan sulphate-rich glycosaminoglycans. The effect of endoglycosidase H suggests that glycopeptides containing oligomannosyl residues linked to N-acetylglucosamine contribute in small degree in maintenance of the negative charge in the BM, but not on the surfaces of the EC. These results show that brain endothelium bears surface anionic domains differing chemically from those described for some fenestrated and continuous endothelia. The distribution of anionic sites indicates that the discrimination against various negatively charged molecules takes place on both fronts of the ECs as well as in the BM of brain micro-blood vessels. The exact role of these domains in the function of the blood-brain barrier remains to be established.
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PMID:Ultracytochemical characterization of anionic sites in the wall of brain capillaries. 274 7

Tritrichomonas mobilensis is a recently described enteric protozoon of squirrel monkeys. An earlier report identified one of the metabolic products of this organism as a lectinlike hemagglutinin. Its further properties were determined in this study. Culture supernatants of T. mobilensis FP4190 were concentrated by ultrafiltration through a membrane with 100,000-molecular-weight cutoff. High titers of agglutinin against human erythrocytes were obtained. Incubation at 70 degrees C for 15 min resulted in complete inactivation. Exposure to 56 degrees C for 30 min was without effect, and only partial loss of activity was obtained during incubation for up to 18 h. Maintenance at pH 4 to 9 for 4 h at room temperature had no deleterious effect. Apparent degradation of the hemagglutinin was achieved by 18 h of contact with proteinase K, but trypsin and collagenase were essentially ineffective. Papain increased the sensitivity of the test. In the presence of this enzyme hemagglutinin was demonstrated also in cultures of Tritrichomonas foetus and Tritrichomonas augusta but not in those of Pentatrichomonas hominis or Trichomonas vaginalis.
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PMID:Basic properties of Tritrichomonas mobilensis hemagglutinin. 317 Jul 9

1. Trypsin digestion of perchloric acid precipitated horse plasma yielded polypeptides with inhibitory properties for trypsin, chymotrypsin and, to a small extent, kallikrein. 2. The Mr of the inhibitory polypeptides were 73,000 and 24,000. 3. The number, enzyme specificity and Mr of the inhibitory polypeptides differed from the values known for the human being. 4. The inhibitory polypeptides were purified by affinity chromatography on Sepharose-trypsin and by gel filtration through Sephadex G-75. 5. Protease inhibitory polypeptides were generated in the same manner by chymotrypsin, elastase, proteinase K, pronase, collagenase, papain and subtilisin. 6. The number and electrophoretic migration of the inhibitory polypeptides obtained with the different enzymes were variable. 7. The enzyme specificity was constant since all polypeptides inhibited only trypsin, chymotrypsin and kallikrein to a small extent. 8. None of the inhibitory polypeptides were immunologically related to native plasma proteins or plasma protease inhibitors.
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PMID:Acid-stable protease inhibiting polypeptides formed from denatured horse plasma by proteolysis. 367 4

Chondroitin sulfate E proteoglycan was extracted in the presence of protease inhibitors from 6 X 10(9) mouse bone marrow-derived, interleukin 3-dependent mast cells, of which 3 X 10(7) had been biosynthetically labeled with [35S]sulfate or [3H]glycine. Chondroitin sulfate E proteoglycan was purified to apparent homogeneity by density-gradient centrifugation, differential molecular weight dialysis, DEAE-52 ion exchange chromatography, and Sepharose CL-4B gel filtration chromatography. Chondroitin sulfate E proteoglycan, radiolabeled with [3H]glycine or [35S]sulfate, filtered as a single peak of radioactivity on Sepharose CL-4B with a Kav of 0.41. When purified [3H]glycine-labeled proteoglycan was digested with chondroitinase ABC and subjected to gel filtration, all of the radioactivity was shifted to a lower molecular weight. As assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis the Mr of the peptide core obtained by chondroitinase ABC treatment was approximately 10,000. The purified proteoglycan was resistant to degradation by collagenase, clostripain, trypsin, chymotrypsin, elastase, chymopapain, V8 protease, proteinase K, and Pronase, as assessed by gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Analysis of the core peptide of the intact proteoglycan revealed that glycine, serine, and glutamic acid/glutamine accounted for 70% of the total amino acids and were present in a molar ratio of 4.3/1.6/1.0. When analyzed for neutral hexose content by gas-liquid chromatography, the proteoglycan contained approximately 2% of its weight as mannose, fucose, galactose, and other sugars, indicating that oligosaccharides were linked to the peptide core. The mouse bone marrow-derived mast cell chondroitin sulfate E proteoglycan, like the rat serosal mast cell heparin proteoglycan, is markedly protease resistant, has highly sulfated glycosaminoglycans, and contains a peptide core that is rich in serine and glycine. These characteristics of the mast cell class of intracellular proteoglycans may contribute to their function in stimulus-induced granule secretion as well as in mediator storage, including retention of cationic neutral proteases.
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PMID:Purification and analysis of the core protein of the protease-resistant intracellular chondroitin sulfate E proteoglycan from the interleukin 3-dependent mouse mast cell. 393 50

A highly unusual collagen was secreted by fibroblasts cultured from 150- and 270-d-old fetal calf nuchal ligaments. Purification revealed that this protein (which may be synthesized in a higher molecular weight form) was precipitated at unusually high concentrations of ammonium sulfate and was also eluted from DEAE-cellulose at greater salt concentrations than were types I and III procollagens. On SDS PAGE, the collagenous protein exhibited an Mr of approximately 12,750 that was not altered in the presence of reducing agent. The low molecular weight collagen (FCL-1) was sensitive to bacterial collagenase and had a [3H]glycine content comparable to that found in type I procollagen, although the [3H]Hyp to [3H]Pro ratio was 0.43. FCL-1 was not cleaved by human skin collagenase, mast cell protease, trypsin, Staphylococcal V8 protease, or proteinase K at 37 degrees C. The collagen was susceptible to trypsin, but not to V8 protease, only after heating at 80 degrees C for 30 min. Preliminary structural studies indicate that FCL-1 was resistant to cleavage by CNBr but exhibited limited proteolysis with pepsin. Both 150- and 270-d-old fibroblasts produced comparable levels of interstitial (types I and III) procollagens, which comprised approximately 70% of the total protein secreted into the culture medium. However, 270-d-old (term) fibroblasts secreted approximately 50% more FCL-1, as percent of total culture medium protein, in comparison to the cells from the earlier gestational stage. This collagen may therefore play a role in the development of the nuchal ligament.
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PMID:Fetal calf ligament fibroblasts in culture secrete a low molecular weight collagen with a unique resistance to proteolytic degradation. 631 46

We have distinguished three fractions of acetylcholinesterase (AcChoE; acetylcholine acetylhydrolase, EC 3.1.1.7) from Torpedo marmorata electric organs, according to their solubilization characteristics. The low-salt-aggregating collagen-tailed forms are soluble in high-salt buffers; their hydrodynamic properties ae not modified in the presence of detergents. They constitute the A fraction, which amounts to about a third of the tissue's AcChoE activity. The low-salt-soluble (LSS) and detergent-soluble (DS) fractions are not sensitive to ionic strength and collagenase. In the presence of nonionic detergents or bile salts, both fractions behave as a monodisperse "6.3S" form, the properties of which have been investigated mostly in the case of Triton X-100. Disulfide bond reduction dissociates the detergent form into a smaller "5S" form. These two forms are thought to be, respectively, detergent-associated dimers and monomers. In the absence of detergent, the LSS fraction is polydisperse: it contains a major 8S component, 11S and 14S components, and faster-sedimenting aggregates, which appear to represent dimers, tetramers, and higher polymers. The heterogeneity of the 8S component in gel filtration suggests that it also contains variable noncatalytic elements. Upon removal of the detergent the DS fraction forms ill-defined aggregates. Trypsin induces quaternary rearrangements of part of the 8S component into 11S and 14S components, which are still convertible into the detergent form; therefore trypsin probably digests noncatalytic elements. Pronase and proteinase K, on the other hand, convert the enzyme into a dimeric form, G2, that does not interact with detergents, probably by cleaving a minor fragment of the subunit that is involved in hydrophobic interactions.
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PMID:Collagen-tailed and hydrophobic components of acetylcholinesterase in Torpedo marmorata electric organ. 693 97

This work presents a filter elution method for measuring DNA single- and double-strand breaks in primary rat hepatocytes without radioactive labeling of DNA. We have studied the effects of a series of nitrosamines and of gamma-irradiation on DNA single- and double-strand break induction. The repair of DNA single-strand breaks in the hepatocytes was measured after treatment with 60Co, 1-methyl-1-nitrosourea, and N-nitrosodimethylamine. The hepatocytes were isolated by ethylene glycol-bis(beta-aminoethyl ether)-N,N'-tetra acetic acid-collagenase perfusion and had a mean viability of 91 +/- 4% (S.D.). The isolated cells were treated for varying lengths of time with nitrosamines in suspension culture in L-15 medium containing 10% fetal bovine serum. After treatment, the cells were chilled, loaded onto 2 micrometers polycarbonate filters, and lysed in a 2% sodium dodecyl sulfate-proteinase K solution, pH 9.6. The DNA was eluted from the filter at either native or denaturing pH with fractions collected every 3 hr. The quantity of DNA in each fraction was determined by measuring the fluorescent product formed between it and diaminobenzoic acid after ethanol-sodium acetate precipitation and trapping of the DNA on 0.2-micrometer polycarbonate filters. The results show that the carcinogens, N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodipropylamine, N-nitrosodibutylamine, and 1-nitrosopiperidine all made dose- and time-related increases in the number of single-strand breaks in rat hepatocytes. N-Nitrosodiphenylamine produced small numbers of single-strand breaks. No double-strand breaks were formed by any of the nitrosamines. Single-strand breaks induced by N-nitrosodimethylamine were repaired very slowly relative to repair of either gamma-ray of 1-methyl-1-nitrosourea-induced single-strand breaks. This system has many advantages for studying carcinogen metabolism and DNA damage in hepatocytes, one of the major target cells for many carcinogens.-
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PMID:Measurements by filter elution of DNA single- and double-strand breaks in rat hepatocytes: effects of nitrosamines and gamma-irradiation. 708 52

An enzyme-linked immunosorbent assay (ELISA) was developed that detects PrP(Sc) in crude extracts from brain and spleen tissue of scrapie-affected mice with high sensitivity and specificity. Brain tissue was homogenized in 8% Zwittergent 3-12 and 0.5% Sarkosyl. The homogenate was treated with collagenase and DNase I and then subjected to proteinase K digestion. Precipitates containing PrP(Sc) were obtained by ultracentrifugation. Spleen tissue was homogenized in 4% Triton X-100 and 0.5% Sarkosyl, and the homogenate was treated firstly with collagenase and DNase I, and secondly with proteinase K. PrP(Sc) was then extracted with 6.25% Sarkosyl and precipitated through salting-out with NaCl and by ultracentrifugation. When PrP(Sc) was dissolved in 3-4 M guanidine thiocyanate and adsorbed to microtiter plates, strong and specific reactions to the formation of antigen-antibody complexes could be detected by ELISA. The sensitivity of PrP(Sc)-detection for this ELISA, as measured by serial dilution of scrapie material in tissue homogenates from uninfected animals, was equal or higher than that attained by Western blot. This ELISA is more rapid than Western blot and seems to be more suitable for screening large numbers of animals. It also has potential application for the diagnosis of the transmissible spongiform encephalopathies.
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PMID:Sensitive enzyme-linked immunosorbent assay for detection of PrP(Sc) in crude tissue extracts from scrapie-affected mice. 907 66

Crude extracts of Leishmania amazonensis, but not of L. guyanensis, are lytic to erythrocytes and nucleated cells, including macrophages. L. amazonensis-mediated lysis is caused by a membrane-associated pore-forming protein, named a-leishporin. Here we show that L. amazonensis, but not L. guyanensis, promastigote extracts increase their hemolytic activity when kept at 4 degrees C for a few days or at 37 degrees C for a few hours. We show that the activation in the extracts is mediated by a cytosolic serine-protease. Although L. guyanensis extracts are hemolytically inactive and unable to generate hemolytic activity, their membrane fraction becomes hemolytic in the presence of the cytosolic fraction of L. amazonensis, also by the action of a serine-protease. This suggests that L. guyanensis contains a potential lytic molecule, named here g-leishporin. The cytosolic fraction of L. guyanensis is unable to activate either a- or g-leishporin, indicating that this species does not possess the protease(s) that activate(s) the cytolysin. Trypsin, chymotrypsin, collagenase, Pronase and proteinase K, are also effective in activating a-leishporin but not g-leishporin. This suggests that the inactive forms of a-leishporin and g-leishporin are distinct in structure and/or are activated by different mechanisms. We are considering two hypotheses for the activation of leishporins: (1) proteolysis of an inactive precursor and (2) dissociation and/or proteolytic degradation of an inhibitory oligopeptide. The present data and preliminary results argue for the second hypothesis. We speculate that leishporin could be activated in the protease-rich, low pH, and dissociating environment of parasitophorous vacuole contributing for the release of the parasites from the macrophage.
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PMID:Proteolytic activation of leishporin: evidence that Leishmania amazonensis and Leishmania guyanensis have distinct inactive forms. 1116 43


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