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:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Collagenase of human basal cell epithelioma was purified by sequential ammonium sulfate precipitation, Sephadex gel filtration and affinity chromatography on collagen-polyacrylamide gel. The collagenase, when partially purified, was found to have an approximate molecular weight of 50,000. The purified enzyme contained no caseinolytic activity. On polyacrylamide gel electrophoresis, the purified enzyme gave a single protein band. The purified collagenase cleaved native acid-soluble guinea pig skin collagen at 37 degrees C with a pH optimum of 8. The enzyme was inhibited by EDTA, cysteine, and human serum but not by soybean trypsin inhibitor. Heparin did not stimulate the enzyme activity. Purified collagenase reduced the specific viscosity of native acid-soluble guinea pig skin collagen to 50 per cent of its original value at 27 degrees C. Polyacrylamide gel disc electrophoresis of the reaction products showed bands corresponding to alphaA, betaA, and alphaB fragments. Electron microscopic examination of SLS aggregates of the reaction products showed that the cleavage site by the enzyme was at a point 75 per cent from the "A" end (TCA75) and 25 per cent from the "B" end (TCB25) of the collagen molecule.
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PMID:Collagenase of human skin basal cell epithelioma. 1 52

Using collagenase digestion as an assay for collagen in partially synchronized secondary cultures of chick embryo fibroblasts, we find that the rate of collagen synthesis remains at a constant fraction of overall protein synthesis (5%) regardless of the growth rate of the cells even when the rate of protein synthesis is accelerated 5-fold by adding serum and altering the pH of the culture medium. However, in cells oncogenically transformed by Rous sarcoma virus, the relative rate of collagen synthesis was decreased by 50% 24 hours after infection and was 10% of the initial rate after 5 days. This selective decrease in rate of collagen synthesis could be reversed in cells infected with an RSV temperature-sensitive transformation-defective mutant at the non-permissive temperature, indicating that the decrease in the rate of collagen synthesis was not merely the result of viral infection but was a direct consequence of oncogenic transformation.
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PMID:Coordinate control of collagen synthesis and cell growth in chick embryo fibroblasts and the effect of viral transformation on collagen synthesis. 1 83

A specific collagenase (EC 3.4.24.3) has been found and purified from serum-free culture medium of 11095 epidermoid carcinoma of rat prostate. The molecular weight of this collagenase was estimated at 71 000 and the pH optimum was approx. 7. At 26 degrees C, the collagenase cleaved collagen at a site 3/4 the length from the N-terminus. At 37 degrees C, this collagenase degraded collagen to smaller peptides. The enzyme activity was inhibited by serum, cysteine and EDTA, but not by protease inhibitors. The presence of collagenase in rat tumor tissue suggests that this enzyme might play a significant role in tissue invasion by cancer cells.
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PMID:Collagenase activity in cultures of rat prostate carcinoma. 3 9

A peptidase cleaving a synthetic substrate for collagen peptidases, 4-phenylazobenzyloxcarbonyl-L-Pro-L-Leu-Gly-L-pro-D-Arg (designated as PZ-peptide) has been purified 1200-fold from rabbit serum and characterized. The enzyme preparation is free of collagenase and unspecific proteinase activity. The natural substrates are denatured collagen and collagen peptides. The peptidase has a molecular weight of 124 000 and an isoelectric point at pH 5.1. The pH dependence curve exhibits two maxima, one at pH 7.1 and the other at pH 7.9. The enzymic reaction is completely inhibited by Zn2+ and to a slower degree by Hg2+, Mn2+ and p-hydroxymercuribenzoate. It is not affected by EDTA and KCN but totally blocked by o-phenanthroline. Phenylmethylsulfonylfluoride is completely inhibitory and points to a serine residue in the active site.
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PMID:Purification and properties of a collagen peptidase (PZ-peptidase) from rabbit serum. 4 Jun 8

A model system consisting of highly purified lysyl oxidase and reconstituted lathyritic chick bone collagen fibrils was used to study the effect of collagen cross-linking on collagen degradation by mammalian collagenase. The results indicate that synthesis of approx. 0.1 Schiff-base cross-link per collagen molecule results in a 2--3-fold resistance to human synovial collagenase when compared with un-cross-linked controls or samples incubated in the presence of beta-aminopropionitrile to inhibit cross-linking. These results confirm previous studies utilizing artificially cross-linked collagens, or collagens isolated as insoluble material after cross-linking in vivo, and suggest that increased resistance to collagenase may be one of the earliest effects of cross-linking in vivo. The extent of intermolecular cross-linking among collagen fibrils may provide a mechanism for regulating the rate of collagen catabolism relative to synthesis in normal and pathological conditions.
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PMID:Native cross-links in collagen fibrils induce resistance to human synovial collagenase. 4 86

The Acinetobacter spec collagenase has been almost completely purified. This enzyme is a true collagenase the activity of which is high on collagen. The enzyme is active on insoluble collagen, gelatin and the synthetic Pz-peptide, but has no proteolytic activity on casein or bovine serum-albumin. The collagenase was obtained on a simple medium with gelatin and yeast extract. The enzyme was purified by (NH4)2SO4 precipitation. DEAE cellulose column chromatography, Sephadex G 200 gel-filtration. The molecular weight of the enzyme was found to be 102 000 daltons, and its isoelectric point was found to be 7,7 +/- 0,2. The optimum pH and temperature for insoluble collagen hydrolysis were 7.6 and 37 degrees C, respectively; so, this collagenase corresponds to true collagenase. Hydrolysis of Pz-peptide is activated by Ca2+ and inhibited by metal ions (Cu2+, Fe3+, Zn2+, Pb2+, Hg2+). EDTA and o-phenanthroline induced a very significant reduction in enzyme activity. Iodoacetate and p-CMB induced a slight reduction in enzyme activity only at high concentrations (10-2M). The collagenase is most stable for temperatures less than or equal to 50 degrees C.
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PMID:[Purification and physico-chemical properties of collagenase synthesized by a bacterium of the type Acinetobacter sp]. 4 44

Rabbit antisera were produced against purified calf dermatosparatic procollagen and against the purified procollagens obtained from the culture medium of calf dermatosparatic cells. These antisera and their derived gamma-globulins were characterized by immunoprecipitation, double immunodiffusion and immunoelectrophoresis. Antiserum directed against dermatosparatic procollagen cross-reacted with the two different forms of procollagen obtained from the culture medium of dermatosparatic calf cells. Antiserum directed against onw of these procollagens, namely (pro alpha1)2 pro alpha2, cross reacted with dermatosparatic procollagen and also cross-reacted with the other procollagen,(pro alpha1)3. Antiserum directed against procollagen (pro alpha1)3 cross-reacted with dermatosparatic procollagen and with the procollagen (pro alpha1)2 pro alpha2. None of the antisera reacted with authentic calf skin collagen, or with the collagen extracted from the cell layer of the dermatosparatic calf cells in culture. Reduction andalkylation of the procollagens abolished the antigen-antibody reactions, while prior digestion of the antigens with bacterial collagenase did not eliminate the immunological reaction. Antigenic determinants in the cell culture procollagens were found at the COOH-terminal non-collagen peptide as well as at the NH2-terminal non-collagen peptide.
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PMID:Immunological properties of procollagens obtained from the culture medium of dermatosparactic cells. 5 Feb 85

It is apparent that significant progress has been made in our understanding of the biosynthesis, modifications, and maturation of collagen and elastin. We now recognize and partially understand special reactions involved in hydroxylations within the cell and complex cross-linking processes occurring outside the cell. Recent experiments (191) have shown that in human diploid fibroblast cultures of limited doubling potential (191) the hydroxylation of collagen prolyl residues appears to be "age" or passage-level dependent. With increasing passage level of these cultures, both the ascorbate requirements and the extent of collagen hydroxylation decrease. "Young" cell cultures have a strong requirement for complete hydroxylation and without ascorbate there is only about 50% of the normal level. "Middle-aged" cultures show higher hydroxylation without and full hydroxylation with ascorbate, whereas "old" (or cultures close to "senescence") are incapable of full hydroxylation with or without ascorbic acid. Although the overall system may show some deterioration with increasing passage levels, it appears that with increasing passage levels other components in the cell replace the ascorbate dependence of the hydroxylase system to a greater exten. In some ways, aging WI-38 cultures begin to resemble some transformed cells in their biochemical reactions, although they continue to remain diploid and eventually lose the ability to replicate. It is not yet known whether old animals can produce collagen, which may now be underhydroxylated, perhaps contributing to certain senescent changes. Careful examination of the hydroxylation index of collagen produced in organoid cultures of tissue biopsies as a function of donor age might be informative, particularly if one looks at the quality of collagen by employing collagenase and other proteolytic digests with collagen (191). One could comare the levels of frequent and characteristic peptide triplet sequences such as Gly-Pro-Hyp to Gly-Pro-Pro, Gly-Ala-Hyp to Gly-Ala-Pro, or Gly-Pro-Hyl to Gly-Pro-Lys and others for evaluation of hydroxylation throughout the entire molecule or at selected sequences.
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PMID:Posttranslational protein modifications, with special attention to collagen and elastin. 5 Jun 3

The occurrence of intracellular fibrillar material (frequently banded) has been studied in normal costal and tracheal chondrocytes of rats at various ages ranging from 1 to 90 days. The study methods have included digestion with collagenase, electron histochemical techniques and routine electron microscopy. Banded fibrillar material has been observed intracellularly in vesicles or in electron-dense bodies in perichondrial and subperichondrial chondrocytes from rats of all ages. These fibrils and extracellular collagen fibrils are partially and equally degradable by collagenase, they are positive after staining with phosphotungstic acid or with silver nitrate methenamine, and their lucency corresponds with that of collagen when they are stained only with lead citrate. They have not been observed in intracellular clefts. They, therefore, seem to be formed intracellularly and to be exocytosed subsequently. Large vesicles and electron-dense bodies seem to be derived from Golgi saccules. A mechanism whereby banded intracellular fibrils could be formed from tropocollagen molecules is postulated. The frequency of occurrence and the diameter of intracellular fibrils seems to increase with increasing age.
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PMID:Periodic fibrillar material in intracellular vesicles and in electron-dense bodies in chondrocytes of rat costal and tracheal cartilage at various ages. 5 69

An inactive collagenase was harvested from both serum-free and serum-supplemented fibroblast monolayer cultures in periods of active collagen synthesis. The latent collagenase did not hydrolyze collagen and did not bind the potent collagenase inhibitor alpha2-macroglobulin. Activation with trypsin imparted to the enzyme the ability to hydrolyze collagen at neutral pH in a typical manner and to form an inhibited complex with alpha2-macroglobulin. The molecular weights, determined by calibrated gel filtration, were 78,000 and 60,000 for the latent and active enzymes, respectively. The data indicate that collagenase is released from the cells in inactive form, as a zymogen.
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PMID:Synthesis and release of procollagenase by cultured fibroblasts. 5 61


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