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)

The specificity of lactoperoxidase-catalyzed iodination for the proteins of the hepatoma tissue culture cell plasma membrane was examined by histochemical, biochemical, and cell fractionation techniques. Light microscope autoradiography of sectioned cells shows the incorporated label to be localized primarily at the periphery of the cell. Most of this label can be released from the cell by trypsin but not by collagenase or hyaluronidase. The label is recovered from the cells as either monoiodotyrosine or diiodotyrosine after hydrolysis of cell extracts with a mixture of proteolytic enzymes. The label co-purifies during cell fractionation with an authentic liver cell plasma membrane marker enzyme, 5'-nucleotidase. Thus, the incorporated iodide is itself a valid marker for those membrane polypeptides having tyrosine residues accessible to the lactoperoxidase. The polypeptide complexity of the purified plasma membrane was examined by high resolution dodecyl sulfate-polyacrylamide gel electrophoresis. At least 50 polypeptides in the membrane are accessible to iodination. These polypeptides probably represent the bulk of the protein mass of the membrane and iodinating them does not affect cell viability, growth rate, or cell function. Labeling experiments with fucose and glucosamine show that at least nine of the iodinated peptides may be glycoproteins.
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PMID:Proteins of the hepatoma tissue culture cell plasma membrane. 0 57

The antibacterial activity of a myeloperoxidase (MPO)-glucose oxidase system was found to be greatly increased by granulocyte elastase, present in azurophil granules of human neutrophils. The MPO-H2O3-mediated killing of both Escherichia coli and Staphylococcus aureus was potentiated by granuocyte elastase at an acid pH, whereas at pH 7.4 only killing of E. coli was potentiated. The potentiating effect of elastase was not dependent on the enzymatic properties of the protein since it was not abolished by heating, which destroys the enzymatic activity. A peptide chloromethyl ketone elastase inhibitor abolished both elastolytic activity and the pctentiating effects on MPO-H2-O2-mediated bacterial killing. The antibacterial activity of chymotrypsin-like cationic protein of human neutrophils was also potentiated by elastase. Other degradative enzymes isolated from human granulocytes, e.g., collagenase and lysozyme, did not potentiate MPO-H2O2-mediated or cationic protein-dependent bacterial killing. The present study indicates that a neutrophil constitutent, elastase, which is not microbicidal by itself, can initiate sublethal changes that render some microorganisms more susceptible to the action of microbicidal agents like MPO and chymotrypsin-like cationic protein.
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PMID:Microbicidal mechanisms of human granulocytes: synergistic effects of granulocyte elastase and myeloperoxidase or chymotrypsin-like cationic protein. 1 11

A method is described that uses trypsin digestion combined with collagenase-hyaluronidase which produces a population of gap junction vesicles. The hexagonal lattice of subunits ("connexons") comprising the gapjunctions appears unaltered by various structural criteria and by buoyant density measurements. The gap junction vesciles are closed by either a single or a double profile of nonjunctional "membrane," which presents a smooth, particle-free fracture face. Horseradish peroxidase and cytochrome c studies have revealed that about 20% of the gap junction vesicles are impermeable to proteins 12,000 daltons or larger. The increased purity of the trypsinized junction preparation suggests that one of the disulfide reduction products of the gap-junction principal protein may be a nonjunctional contaminating peptide. The gap junction appears to be composed of a single 18,000-dalton protein, connexin, which may be reduced to a single 9,000-dalton peak. The number of peptides in this reduced peak are still unknown.
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PMID:In vitro formation of gap junction vesicles. 5 58

Submandibular glands of 4-week-old rats were dissociated by a procedure involving digestions with collagenase and hyaluronidase, chelation with ethylenediaminetetraacetic acid, and mechanical force. The isolated cells were purified by centrifugation in a Ficoli solution and were maintained in culture for 36 hours. On the basis of trypan blue exclusions, about 70 per cent of the dissociated cells were viable. Electron microscopic observations indicated that the isolated acinar cells and intercalated and striated duct cells retained their essential in situ ultrastructural characteristics. During a 36-hour culture period the number of viable cells declined to about 40 per cent, and the various cell types formed mixed aggregates. The ultrastructural features of the intercalated and duct cells changed relatively little, but the acinar cells revealed several structural alterations. These included a decrease in the number of the secretory granules, fusions of the secretory granules, and an increase in the rough surfaced endoplasmic reticulum. In general, the polarity of acinar cells became less distinct. The endogenous peroxidase activity in the acinar cells gradually diminished during the culture. Isoproterenol when added to the cultured cells failed to stimulate the incorporation of radioactive thymidine or the discharge of the secretory material from the acinar cells.
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PMID:Short term culture of dissociated rat submandibular gland cells. 16 89

The relationship between activation of resting chick embryo fibroblasts by proteases and proteolytic alteration of the cell surface has been investigated. Five different proteases were examined: trypsin, collagenase, plasmin, alpha-chymotrypsin, and thrombin. All of these proteases, when added to the culture medium at concentrations of 0.08-2.2 mug/ml, stimulated deoxyglucose uptake and induced cell division. The absolute levels of stimulation depended on the specific protease. Activation ranged from a doubling in cell number in 24 hr for trypsin and thrombin down to a 47% increase in cell number for alpha-chymotrypsin. Except in the case of thrombin, the stimulatory effects of these proteases correlated with breakdown of Z, a protein which is the major chick surface protein as revealed by lactoperoxidase-catalyzed iodination and which disappears upon transformation. In the case of thrombin, stimulatory concentrations brought about no detectable loss of surface components. Thus loss of Z is not a necessary condition for activation of chick fibroblasts; it may be a sufficient condition for activation of part of the cell population.
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PMID:Effect of proteases on activation of resting chick embryo fibroblasts and on cell surface proteins. 17 Oct 80

The possible direct role of inflammatory cells in resistance to Trichinella spiralis was studied by observing the effects of lamina propria cells from the small intestine (LP cells) of immunized rats on various stages of the parasite. Effects produced by physically disrupted cells were compared to those produced by intact cells on worms exposed to phytohemagglutinin or immune serum. LP cells were isolated from the rat intestine by collagenase digestion of everted gut segments that were previously denuded of epithelium by treatment with hyaluronidase. Disrupted cells, but not intact ones, selectively killed T. spiralis juvenile and adult worms in vitro, whereas larvae were unaffected by similar treatment. Attempts to identify the lethal component of disrupted cells led to an evaluation of the enzyme, peroxidase. Mucosal peroxidase is localized in LP cells and its activity increases several-fold during intestinal trichinosis. It is presumed to be myeloperoxidase, a particulate-bound enzyme of myeloid-derived leukocytes that functions as part of a potent antimicrobial system in combination with H2O2 and a halide. Results indicated that the vermicidal component of LP cells was associated with the pellet fraction of disrupted centrifuged LP cells, but was not linked to a peroxidase-H2O2-halide system.
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PMID:Lethality of disrupted intestinal lamina propia cells for Trichinella spiralis in vitro. 17 21

The subcellular localization of granulocyte collagenase, elastase and chymotrypsin-like cationic protein was determined using velocity centrifugation of cytoplasmic granules of human polymorphonuclear leukocytes. The proteases were assayed by immunochemical and enzymatic methods. Measurements of lactoferrin and myeloperoxidase distinguish exactly between constituents of specific and azurophil granules. Collagenase, elastase and chymotrypsin-like cationic proteins showed an almost identical sharp and unimodal distribution. They co-sedimented with myeloperoxidase demonstrating that these enzymes are localized exclusively in the azurophil granules.
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PMID:Localization of chymotrypsin-like cationic protein, collagenase and elastase in azurophil granules of human neutrophilic polymorphonuclear leukocytes. 19 54

Human granulocytes release 25-30% of the granular neutral proteases, collagenase and elastase, to the exterior of the cell during phagocytosis of yeast cells or immune complexes. Similar amounts of myeloperoxidase and lactoferrin are released. Crossed immunoelectrophoresis demonstrated that collagenase and elastase released extracellularly formed complexes with serum alpha1-antitrypsin. The presence of alpha1-antitrypsin complexes with granulocyte collagenase and elastase were also demonstrated in inflammatory processes, e.g. in the peritoneal exudate of acute peritonitis. The reactivity of neutrophil proteases with natural plasma protease inhibitors must be considered in assessing the role of these proteases as the etiologic agent of tissue damage and degradation during the inflammatory process.
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PMID:The extracellular release of granulocyte collagenase and elastase during phagocytosis and inflammatory processes. 19 89

The intraneutrophilic concentrations of lactoferrin, myeloperoxidase, collagenase and chymotrypsin-like cationic proteins were measured sequentially during acute bacterial infection. The serum levels of lactoferrin and myeloperoxidase were also followed as well as the 'eosinophil' cationic protein as a marker for eosinophil leucocytes. During the early course of infection there was a profound but reversible decrease of intraneutrophilic lactoferrin. The levels of cellular collagenase and chymotrypsin-like cationic proteins also tended to decrease reversibly during day 2-8 in most cases; myeloperoxidase levels were normal except for two cases. Serum myeloperoxidase and lactoferrin correlated with blood neutrophil counts. In spite of the absence of peripheral eosinophils the 'eosinophil' cationic proteins of serum were increased on the first day of infection, which may reflect increased eosinophil turnover.
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PMID:Neutrophil and eosinophil granulocytes in bacterial infection: sequential studies of cellular and serum levels of granule proteins. 20 75

The extracellular release from human neutrophils of the primary (azurophil) granule constituents, myeloperoxidase (MPO), chymotrypsin-like cationic protein (CCP), collagenase and lysozyme, and the secondary (specific) granule constituents, lactoferrin and lysozyme, was measured during ingestion of staphylococcus protein-A-IgG complexes. In buffer, lactoferrin release was consistently higher than that of the other protein. In serum, lactoferrin release increased concomitantly with ingestion, whereas the rate of lysozyme and especially of MPO release were stimulated to a higher degree than ingestion. Magnesium (0.5--2 mM) was more potent than calcium (0.5--2 mM) in promoting release but these cations worked synergistically. Zinc (0.5--4 mM) was found to be a potent and selective inhibitor of collagenase release. Manganese (0.25--4 mM), which inhibited the ingestion of SpA-IgG complexes, also inhibited release of CCP, collagenase, lysozyme and MPO, but actually stimulated lactoferrin release. The data suggests that lactoferrin and lysozyme may be confined to distinct granule populations or else released in a different fashion from the granules. When the effects on release of primary granule proteins are concerned it is suggested that the dissociation of binding of various agents to an anionic granule matrix may be affected differently by various cations.
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PMID:Effects of serum and cations on the selective release of granular proteins from human netrophils during phagocytosis. 22 47


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