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)

From the supernatant of B. melaninogenicus ss. asaccharolyticus culture, a protein fraction was isolated by ethanol precipitation. The fraction was tested for the presence of clotting and fibrinolytic activities by application of quantitative techniques and specific substrates for measurement of prothrombin and plasminogen activation, and collagenase and elastase activity. It is postulated that ability of Bacteroides melaninogenicus ss. asaccharolyticus extracellular factors to clot fibrinogen and activate plasminogen, are due to a limited proteolysis by the proteolytic enzymes produced by this microorganism and not to the existence of specific B. melaninogenicus coagulase of plasminogen activator.
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PMID:The nature of clotting and fibrinolytic activities of Bacteroids melaninogenicus. 2 65

To elucidate the mechanism of synovial damage in rheumatoid arthritis, we studied the activation of latent collagenases released from adherent rheumatoid synovial cells in culture. Latent enzyme was not complexed with alpha2 macroglobulin, the prinicpal proteinase inhibitor in serum, and could be activated by trypsin in the presence of alpha2 macroglobulin if sufficient proteinase was added to saturate inhibitor. Latent collagenase bound half as effectively to collagen fibrils as active enzyme. Plasmin was a threefold better activator of latent enzyme than trypsin and could be generated by addition of plasminogen to synovial-cell cultures. Production of both collagenase and plasminogen activator was inhibited by dexamethasone (10(-9) M). These studies emphasize in importance of control of activation in regulation collagenase activity, It is likely that rheumatoid synovium produces both latent collagenase and plasminogen activator; plasmin is activated from its zymogen, plasminogen, present in inflamed tissues, and in turn activates collagenase.
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PMID:Endogenous activation of latent collagenase by rheumatoid synovial cells. Evidence for a role of plasminogen activator. 6 27

Mononuclear phagocytes secrete a number of materials into the extracellular environment. The materials secreted by phagocytes can be grouped into three categories: a) enzymes affecting extracellular proteins (collagenase, elastase, lysosomal proteases, plasminogen activators), b) materials involved in defense processes (complement proteins, interferons, lysozyme), and c) factors regulating activities of surrounding cells. The latter include lymphostimulatory molecules, a colony-stimulating factor, and inhibitors of cell growth. The conditions for secretion of the materials depend on the activity of the phagocytes. The lymphostimulatory molecules secreted by macrophages exert various effects: 1) an increase in DNA synthesis of lymphocytes, 2) a maturation of early thymocytes to mature T cells, and 3) the differentiation of some B cells to antibody-secreting cells. The mitogenic principle has been partially isolated as a protein of 15,000 to 20,000 daltons. The secretion of lymphostimulatory molecules is increased following uptake of various materials by macrophages or by addition of activated T cells to macrophage cultures.
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PMID:Regulation of immunity and inflammation by mediators from macrophages. 13 1

Reaction mixtures of human serum and increasing amounts of granulocyte collagenase, elastase and chymotrypsin-like enzyme were studied by crossed immunoelectrophoresis utilizing antibodies against alpha1-antitrypsin, alpha1-antichymotrypsin, and antiplasmin. The increasing complex formation of alpha1-antitrypsin and alpha 1-antichymotrypsin with the different granulocyte proteases was not accompanied by any changes in the electrophoretic mobility or precipitate pattern of antiplasmin until the protease binding capacity of serum was saturated. The antiplasmin component in the reaction mixtures of human serum and granulocyte collagenase or elastase was not precipitated by antibodies against the proteases. The results indicate that none of the granulocyte proteases are bound by antiplasmin and that these enzymes do not activate plasminogen in serum.
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PMID:Comparison of the reactions of neutral granulocyte proteases with the major plasma protease inhibitors and with antiplasmin. 21 Apr 94

The c-ets1 proteins are transcriptional activators expressed within endothelial cells during blood vessel development in chick embryos. The authors show by in situ hybridization that c-ets1 is transcribed in the endothelia during angiogenesis in human embryos, in granulation tissue, and especially during tumor vascularization. c-ets1 mRNAs were also detected in the fibrocytes of tumor stroma and in the spindle cells of Kaposi's sarcomas, regarded as cells of endothelial origin. It has been shown that the c-ets proteins activate transcription through a PEA3 motif that plays a role in the stimulation of transcription of urokinase-type plasminogen-activator (u-PA), stromelysin and collagenase genes. The authors demonstrate in vitro that the angiogenic factor TNF alpha increases transiently the amount of both c-ets1 and u-PA mRNA in confluent human umbilical vein endothelial cells. Therefore, the authors suggest that the c-ets1 proteins might regulate the transcription of the genes coding for matrix-degrading proteases, which are necessary for both angiogenesis and tumor invasion.
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PMID:c-ets1 proto-oncogene is a transcription factor expressed in endothelial cells during tumor vascularization and other forms of angiogenesis in humans. 137 May 94

There are two types of collagenases, products of two distinct genes, called MMP-1 (matrix metalloproteinase 1 or "fibroblast-type collagenase") and MMP-8 ("neutrophil collagenase"). In synovial fluid, MMP-8 is stored as latent proenzyme in polymorphonuclear neutrophils. MMP-8 is activated by hypochlorous acid produced by myeloperoxidase from hydrogen peroxide and chloride ion and by the hydroxyl radical produced in Haber Weiss reaction fed by superoxide produced by, eg, NADPH (reduced nicotinamide adenine dinucleotide) oxidase and xanthine oxidase. In addition to activation upon secretion, oxidatively modified MMP-8 is susceptible to a subsequent proteolytic attack and activation by cathepsin G. The authors suggest that activation of neutrophil-derived MMP-8 involves oxidative, nonproteolytic activation upon secretion and a more slowly progressive proteolytic activation by cathepsin G (or chymases and tryptases), and that these oxidative and proteolytic activation mechanisms act in concert. In contrast to MMP-8, MMP-1 is synthesized de novo and secreted immediately after synthesis by fibroblasts, macrophages, and some epithelial cells. Human rheumatoid synovial tissue contains mainly fibroblast-type MMP-1 collagenase as assessed by collagenase extracted from synovial tissue and by MMP-1 and MMP-8 immunostaining. It is suggested that in vivo, MMP-1 in synovitis tissue is activated by a plasminogen activator/plasminogen/prostromelysin (alternatively tryptases)/proMMP-1 cascade. In conclusion, MMP-8 and MMP-1 show type-specific compartmentalization and modes of activation in rheumatoid synovial fluid and tissue.
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PMID:Collagenase in synovitis of rheumatoid arthritis. 141 81

We have examined the conditions for dissolution by live cells of an extracellular matrix composed of reconstituted type I collagen fibrils, using three different cell types which express varying constitutive or inducible levels of procollagenase and collagenase inhibitor. The two major conclusions from these studies were that (i) expression of collagenase is a necessary but not sufficient requirement for dissolution of the collagen fibrils and that (ii) activation of procollagenase is a rate-limiting step. Cells which secreted high levels of procollagenase dissolved collagen fibrils only to the extent that they were able to activate the enzyme. Cells which also expressed inhibitor failed to activate procollagenase in the culture medium and did not dissolve the collagen fibrils unless procollagenase-activation was assisted by exogenous proteinase activity. Cells that did not express inhibitor ultimately did activate procollagenase but the process was slow and incomplete. Introduction of exogenous proteinase activity either in the form of plasminogen, plasmin, or trypsin stimulated collagen breakdown by several fold. Analysis of the culture medium sampled from such cultures showed that the stimulating effect of exogenous proteinases could be ascribed to three separate, but synergistic events: elevated expression of procollagenase, conversion of procollagenase to active form and inactivation of collagenase inhibitor. Two lines of evidence suggested that the dissolution of collagen fibrils in these cultures was mediated by a collagenase-dependent pathway: (i) the rate of dissolution closely mirrored the level of expression of collagenase and (ii) the process was blocked by inhibitory collagenase-specific antibodies.
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PMID:Degradation of collagen fibrils by live cells: role of expression and activation of procollagenase. 148 62

Chinese hamster ovary (CHO) cells were examined for production of an enzyme that nicked the polypeptide chain of the heat-labile enterotoxin from enterotoxigenic Escherichia coli between the A1 and A2 fragments of its A subunit. Serum-free culture medium prepared each day after CHO cell inoculation was concentrated 100 times and its proteolytic activity for formation of the A1 fragment was examined by Western blotting with anti-LT A antibody. The A subunit was detected in culture medium on day 6 after cell inoculation, although not in media on day 1 or 3, indicating that CHO cells produced a nicking enzyme. This nicking enzyme had an optimal pH of about 7.5 and an apparent Mr. of 120,000, as seen by Superose 12 TM gel filtration with an FPLC system. The activity of this enzyme was strongly inhibited by diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride, but not by p-chloromercuribenzoic acid, EDTA or ethyleneglycol bis (beta-aminoethylether)-N,N-N',N'-tetraacetic acid, suggesting that this enzyme was a serine protease. The activity was not stimulated by plasminogen or fibrin. These findings suggest that the nicking enzyme was different from proteases such as elastase, collagenase and plasminogen activator, which are probably also secreted by fibroblast-like CHO cells.
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PMID:Chinese hamster ovary cells produce an enzyme that nicks heat-labile enterotoxin from enterotoxigenic Escherichia coli. 157 34

Mediators released from injured human skin that initiate the inflammatory response have not been adequately identified. Organ culture of full-thickness skin explants enables us to do so, because injury to the skin can be made in vitro, eliminating the rapid leakage of serum and infiltration of leukocytes that occur in vivo. In our studies, the military vesicant sulfur mustard (SM) (10 microliters of a 0.01 to 1.0% dilution) was topically applied to injure the epidermis of the explant. Then, the explants were cultured in small Petri dishes, usually for 18 h at 36 degrees C, and the organ-culture fluids were assayed for various inflammatory mediators. We found that the culture fluids from SM-exposed and control explants contained similar amounts of angiotensin-converting enzyme, trypsin-like and chymotrypsin-like proteases, acid phosphatase, beta-glucuronidase, beta-galactosidase, lysozyme, deoxyribonuclease, ribonuclease, interleukin 1, and lactic dehydrogenase. However, the culture fluids from SM-exposed explants contained increased amounts of histamine and plasminogen-activating activity, and often prostaglandin E2, when compared to culture fluids from control explants. After 3 to 4 d in culture, full-thickness human skin explants, when exposed to 0.2% SM (but not when exposed to 1.0% SM), sometimes showed separation of the epidermis and increased collagenase activity (i.e., hydroxyproline release). Thus, histamine (from local mast cells), and prostaglandin E2 and plasminogen-activating activity (probably from both mast cells and epidermal cells) are apparently involved in early mediation of the inflammatory response.
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PMID:Mediators, initiating the inflammatory response, released in organ culture by full-thickness human skin explants exposed to the irritant, sulfur mustard. 171 Jun 39

Laminin is a large multidomain glycoprotein with diverse biological activities which include stimulation of neurite outgrowth, enhancement of tumor metastasis, and promotion of cell growth, adhesion, and differentiation. A 19 amino acid synthetic peptide derived from the E8 fragment of the laminin A chain (Cys-Ser-Arg-Ala-Arg-Lys-Gln-Ala-Ala-Ser-Ile-Lys-Val-Ala-Val-Ser-Ala-Asp -Arg- NH2) was identified which promotes metastasis and stimulates collagenase IV activity in the culture medium of B16 melanoma cells (Kanemoto et al., 1990). We report that this peptide, here designated LamA2091-2108, is also a potent stimulator of tissue plasminogen activator (t-PA)-catalyzed plasminogen activation, resulting in a 22-fold increase in the kcat/Km of the activation reaction. The activity of purified type I and type IV collagenase was inhibited by LamA2091-2108 with IC50 values of 3 and 43 microM, respectively. These data support an alternative mechanism for the appearance of collagenase activity in the culture media of melanoma cells, namely, that the peptide stimulates plasminogen activation, subsequently generating collagenase activity.
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PMID:Modulation of plasminogen activation and type IV collagenase activity by a synthetic peptide derived from the laminin A chain. 184 24


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