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

---

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

Hydroxyproline-containing structural glycopeptide fractions were isolated from collagenase-digested neutral salt-insoluble collagen of five-day sponge-implant connective tissue of the rat. The glycopeptide fractions characterized migrate as a single, strongly anionic band on disc gel electrophoresis at pH 9.5, are eluted on gel filtration as a small molecular weight peak, approximately 2000, and are resolved into thirteen glycopeptide fractions by DEAE-cellulose chromatography. Amino acid analyses of some of these fractions indicate a similarity in composition, the principal ones being aspartic and glutamic acids, serine, glycine, alanine, valine, proline and hydroxyproline. Three neutral carbohydrates, glucose, mannose and xylose, in different relative proportions and hexosamine are also present in the fractions. Amino-terminal amino acid determinations indicate a microheterogeneity of the glycopeptides. The electrophoretic behaviour and non-diffusibility of the small molecular weight glycopeptides suggest an intimate association between acidic hydroxyproline-containing peptides and carbohydrate components of developing connective tissue.
...
PMID:Hydroxyproline-containing structural glycopeptide fractions from subacute inflammation connective tissue. 17 78

Arthritis was induced by injecting cationic amidated bovine serum albumin (aBSA) (pI approximately 9.2) into the knee joint of immunized guinea pigs and the mechanisms of articular cartilage destruction were studied morphologically and biochemically. Marked synovitis associated with polymorphonuclear leukocyte (PML) infiltration occurred within 1 day of the challenge. Articular cartilage infiltrated by PMLs was almost completely destroyed after 2 weeks. During the initial destructive process, proteoglycans were depleted from the cartilage and later collagen fibers disappeared. Granulation tissue growing in the inflamed synovium and bone marrow replaced the destroyed cartilage and joint cavity and formed fibrous scar tissue (fibrous ankylosis) by 8 weeks. Subsequently, the knee joints developed cartilagenous ankylosis by 12 weeks and finally bony ankylosis at 28 weeks. Autoradiography using 125I-aBSA and immunofluorescence studies for immunoglobulin (IgG) and complement (C3) demonstrated that the antigen is trapped in all zones of the articular cartilage and serves as a trigger for immune complex formation. Significantly increased neutral proteinase activities against substrates of proteoglycan subunits, [3H]carboxymethylated transferrin and L-pyroglutamyl-L-prolyl-L-valine-paranitroanilide were detected in homogenates of the synovium and cartilage from arthritic knee joints 1 and 2 weeks after induction. Inhibitor studies and pH curves suggested that the proteinase is leukocyte elastase. Measurable amounts of gelatinolytic activity, detected by activation with 4-aminophenylmercuric acetate and inhibited with EDTA, were also present in the same samples, but there was no detectable collagenase activity. The data on SDS-gelatin substrate gel showed that the proteinase is gelatinase derived from PMLs. These results suggest that in aBSA-induced arthritis, elastase and gelatinase from PMLs invading articular cartilage may play important roles in cartilage destruction.
...
PMID:Arthritis induced immunologically with cationic amidated bovine serum albumin in the guinea pig. A morphological and biochemical study on the destruction of articular cartilage. 167 78

Experimental autoimmune glomerulonephritis (EAG) in chickens appears to be mediated by cellular immunity and is associated with mesangial proliferation. We have developed techniques for the culture of chicken mesangial cells to study factors in vitro which lead to this proliferation. Chicken glomeruli isolated by sieving collagenase-treated whole kidney homogenates were cultured in Waymouth's medium MB 752/1 supplemented with 20% decomplemented fetal calf serum and 1 unit/ml insulin. Propagated cells share the following characteristics with mammalian mesangial cells: stellate and spindle-shaped morphology with an extensive microfilamentous system by light and electron microscopy; resistance to aminonucleoside of puromycin; susceptibility to mitomycin C; growth in L-valine-free medium; absent staining for factor VIII-related antigen, chicken T cell and Ia antigen; positive staining for fibronectin, myosin, alpha-actinin and desmin, and angiotensin II binding and induction of contraction. Unlike cultured mammalian mesangial cells, chicken mesangial cells avidly phagocytize latex beads and display multilamellar residual bodies on electron microscopy indicative of phagocytic activity. They differed from fibroblasts which were non-phagocytic, had different growth patterns, fluorescence staining and ultrastructural morphology. To our knowledge, this is the first description of the culture of chicken mesangial cells. This in vitro system should allow further studies of pathogenetic processes involved in the production of EAG with elucidation of mechanisms relevant to human disease.
...
PMID:Isolation and characterization of chicken mesangial cells. 185 85

Two substitutions for glycine in the triple-helical domain were found in type I procollagen synthesized by skin fibroblasts from two probands with lethal osteogenesis imperfecta. One was a substitution of valine for glycine alpha 1-637, and the other was a substitution of arginine for glycine alpha 2-694. The effects of the mutations on the zipper-like folding of the collagen triple helix were similar, since there was post-translational overmodification of the collagenase A fragments (amino acids 1-775) but not of more COOH-terminal fragments of the protein. The mutations differed markedly, however, on their effects on thermal unfolding of the triple helix. The collagenase A fragment from the collagen containing the arginine alpha 2-694 substitution was cleaved at about amino acid 700 when incubated with trypsin at 30-35 degrees C. Therefore, there was micro-unfolding of the triple helix at a site close to the glycine substitution. Surprisingly, however, the collagenase A fragment with the valine alpha 1-637 substitution was also cleaved at about amino acid 700 under the same conditions. The results, therefore, demonstrated that although most glycine substitutions delay folding of the triple helix in regions that are NH2-terminal to the site of the substitution, the effects on unfolding can be transmitted to regions that are COOH-terminal to the site of the glycine substitution.
...
PMID:Substitutions for glycine alpha 1-637 and glycine alpha 2-694 of type I procollagen in lethal osteogenesis imperfecta. The conformational strain on the triple helix introduced by a glycine substitution can be transmitted along the helix. 187 19

Enzyme treatment of the corneal endothelium with collagenase was employed in a new method of isolating human corneal endothelial cells (HCEC) from the corneas of adult donors (30-70 years). It was possible to isolate 5-10 X 10(4) endothelial cells from each cornea, and primary cultures were established. During the first 3-5 passages, the growth of contaminating fibroblast like cells was inhibited by the use of an L-valine-free selective culture medium. Proliferation of the cells was stimulated by supplementation of the culture medium with fibroblast growth factor and also by coating the culture dishes with a mixture of laminin and chondroitin sulfate. After 3-6 passages, the cell number had increased 150-200 times. During the passage the cells changed with regard to their typical morphology. This change depended on the amounts of serum and mitogen, respectively, in the culture medium, as well as on the in vitro age of the cells.
...
PMID:[Growing human corneal endothelium in cell culture]. 265 38

Human corneal endothelial cells (HCEC) were isolated by means of enzymatic treatment of excised corneas. The corneas were incubated for 1.5 hr together with a high concentration of collagenase (0.5%), followed by a long-term incubation (up to 16 hr) using a low concentration of the enzyme (0.04%). Endothelial cells were enriched against contaminating fibroblasts by using a selective L-valine-free medium which inhibited fibroblast growth during the first passages. Subcultures of HCEC were passaged for more than 20 generations without showing signs of senescence. Laminin and chondroitin sulfate functioned as a substrate for HCEC, promoting proliferation and allowing the cells to grow in monolayer formation. The inclusion of fibroblast growth factor (FGF) as well as chondroitin sulfate in the medium led to an additional increase in the rate of proliferation.
...
PMID:Isolation and long-term cultivation of human corneal endothelial cells. 318 1

Hepatocytes were isolated from livers of fasted rats by a two-step Ca++-free/collagenase perfusion method. Suspensions of parenchymal liver cells were incubated in the absence and presence of three different anaesthetics, diethyl ether, pentobarbital and fentanyl at various concentrations. Their influence on the hepatocytes was monitored by measuring protein synthesis as the incorporation of L-(U-14C) valine (50 mCi/mol, 4.2 mM) into liver proteins. Diethyl ether representing anaesthetics mainly affecting cellular membranes unspecifically, inhibited protein synthesis markedly, concentrations of approximately 10, 20 and 30 mM caused 27, 50 and 74 per cent inhibition respectively, of cellular protein synthesis. The rate of synthesis process of these proteins or that ether also inhibited protein secretion from cells to media. The effect of diethyl ether was completely reversible when the anaesthetic was removed by changing the medium. Pentobarbital representing barbiturate anaesthetics, reduced the synthesis of cell and medium proteins very little, while the opiate anaesthetic fentanyl had no inhibitory effect. These results demonstrate a potential hepatotoxic mechanism for membrane active drugs like diethyl ether. They also indicate that special precautions should be taken when this type of anaesthesia is used during the study of hepatic protein synthesis.
...
PMID:Effects of anaesthetics on protein synthesis in isolated rat hepatocytes: inhibition by diethyl ether in contrast to no influence by pentobarbital and fentanyl. 405 Apr 52

The two morphologically different constituents of the mature elastic fiber, the central amorphous and the peripheral microfibrillar components, have been separated and partially characterized. A pure preparation of elastic fibers was obtained from fetal bovine ligamentum nuchae by extraction of the homogenized ligament with 5 M guanidine followed by digestion with collagenase. The resultant preparation consisted of elastic fibers which were morphologically identical with those seen in vivo. The microfibrillar components of these elastic fibers were removed either by proteolytic enzymes or by reduction of disulfide bonds with dithioerythritol in 5 M guanidine. The microfibrils solubilized by both methods were rich in polar, hydroxy, and sulfur-containing amino acids and contained less glycine, valine, and proline than the amorphous component of the elastic fiber. In contrast, the amino acid composition of the amorphous component was identical with that previously described for elastin. This component demonstrated selective susceptibility to elastase digestion, but was relatively resistant to the action of other proteolytic enzymes and to reduction. These observations establish that the microfibrils consist of a different connective tissue protein (or proteins) that is neither collagen nor elastin. During embryologic development the microfibrils form an aggregate structure before the amorphous component is secreted. These microfibrils may therefore play a primary role in the morphogenesis of the elastic fiber.
...
PMID:The elastic fiber. I. The separation and partial characterization of its macromolecular components. 581 69

Monocellular suspensions of epithelial cells from mammary glands of rabbits at 20-22 days of pregnancy were prepared by sequential dissociation with collagenase-hyaluronidase followed by Pronase. Maintenance in D-valine-substituted minimum essential medium (D-valine-MEM) supplemented with 10% dialyzed calf serum yielded monolayers enriched for rabbit mammary epithelial cells (RMEC). RMEC specifically and reversibly bound bovine PRL with Ka = 1.41-1.85 x 10(9)M-1. Association of lactogen with RMEC receptor followed bimolecular reaction kinetics with rate of 5.17 (+/- 0.75) x 10(5)M-1 sec-1 at 24 C, and 1.03 (+/- 0.11) x 10(6)M-1 sec-1 at 37 C. Dissociation was first order (K-1 = 5.97 (+/- 0.70) x 10(-5) sec-1) and was unaffected by the presence of lactogen. Specific binding determined with an excess of unlabelled bPRL was 66-77% of the total binding, and was optimal at pH 7.4. The binding reaction reached equilibrium in 2 h at 37 C, in 3 h at 24 C, and after 24 h at 4 C. Studies of binding capacity revealed the presence of 4.6-6.3 x 10(3) sites per cell, competition for which was limited to hormones demonstrating lactogenic activity. Recovered lactogen was not degraded by incubation with or dissociation from RMEC. Approximately 25% of the radioactivity remained associated with the cells even upon prolonged incubation. These studies demonstrated several advantages of RMEC for the investigation of hormone-receptor interaction and receptor regulation.
...
PMID:Kinetic characterization of [125I] iodo-prolactin in binding to primary monolayer cultures of rabbit mammary epithelium. 628 30

(1) Glucose stimulates the incorporation of amino acids into protein in lung cells isolated by digestion of the lung stroma with collagenase. This effect reflects mainly an increase in protein synthesis since no effect of glucose had been found to the uptake of amino acid precursors and, although glucose decreases the rate of intracellular proteolysis by 15%, this effect cannot account for the increased incorporation of radioactivity into proteins. Furthermore, glucose did not induce any significant change in the intracellular content of valine. (2) For glucose to act on protein synthesis, it must be glycolyzed since its stereoisomer, L-glucose, which is not metabolized by lung cells, has no effect. (3) The mechanism of glucose action does not seem to be related simply to variations of cellular ATP content or energy charge. The following arguments seem to support this conclusion: (i) glucose does not bring about significant variations in the concentration of reactants of the adenylate system; (ii) the increase in protein synthesis induced by glucose in energy-depleted cells correlates with a rise in ATP content and energy charge; however, adenosine, which increases ATP levels in a form quantitatively similar to glucose, is unable to affect protein synthesis: (iii) glucose also accelerates the incorporation of amino acids into proteins in adenosine-treated lung cells in which the ATP concentration was almost double that of the control and the energy charge was considerably elevated, ruling out the possibility that a rise in the steady-state concentration of ATP and/or energy charge alone could be responsible for the acceleration of protein synthesis. (4) It can be concluded that the effect of glucose in increasing protein synthesis in lung cells is dependent on some signal arising from its breakdown and not to variations in the concentration of reactants or energy charge of the adenylate system.
...
PMID:Role of the adenylate system and glycolytic flux in the control of protein synthesis in isolated rat lung cells. 629 28


1 2 3 Next >>

---