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

Studies were performed to determine if cultured human endothelial cells synthesized basement membrane collagen. In culture, endothelial cells were attached to grossly visible membranous structures which on light microscopy were composed of ribbons of dense, amorphous material. On transmission electron microscopy, these membranous structures consisted of amorphous basement membrane, and material morphologically similar to microfibrils and elastic fibers. By immunofluorescence microscopy, these membranous structures stained brightly with antisera to human glomerular basement membrane. Cultured endothelial cells incorporated [3H]proline into protein; 18% of the incorporated [3H]proline was solubilized by purified collagenase. When endothelial cells were cultured with [14C]proline, 7.1% of the incorporated counts were present as [14C]hydroxyproline. Cultured endothelial cells were labeled with [3H]glycine and [3H]proline and digested with pepsin. The resulting fractions on analysis by SDS-polyacrylamide gel electrophoresis contained two radioactive protein peaks of mol wt 94,200 and 120,500. Both these peaks disappeared after digestion with purified collagenase. The peak of mol wt 120,500 corresponds to that of alpha1 (IV) collagen; the peak of the mol wt 94,200 probably corresponds to that of alpha1 (III) collagen. Thus, cultured human endothelial cells synthesize material which is morphologically and immunologically like amorphous basement membrane and biochemically like basement membrane collagen. Cultured endothelial cells probably also synthesize material which is morphologically similar to microfibrils and elastic fibers.
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PMID:Synthesis of basement membrane collagen by cultured human endothelial cells. 5 57

A method for primary culture of ovine myometrial cells is described. After dissection, myometrium of ewe uteri was digested in trypsin and collagenase. The cells were preplated for 1 h at 37 degrees C. The non-attached cells were grown in appropriate medium supplemented with 2% fetal calf serum. They had a doubling time of 3 days, reached confluency at 10 days and did not exhibit contact inhibition. Cultures were maintained up to 22 days. Characterization of the cells was achieved by electron microscopy, analysis of myosin in cell extracts and assessment of hormone sensitivity. The cells were found to contain myofilaments, characteristic of smooth muscle. A high content of myosin (6--13%) was demonstrated on SDS-polyacrylamide gel electrophoresis: this was confirmed by ATPase activity assay. Cells responded to estradiol stimulation by increased protein synthesis, and bound [3H]estradiol in a specific and saturable way. These results suggest that myometrial cells grown in primary culture should provide a useful model for studying the hormonal control of contractile protein synthesis.
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PMID:Myometrial cells in primary culture: characterization and hormonal profile. 15 21

Proteoglycan complexes from collagenase [EC 3.4.24.3]-indigestible materials of bovine heart valves were extracted with 4 M guanidinium chloride, purified by ion-exchange column chromatography in a urea-containing solution, then fractionated by density-gradient centrifugation under dissociative conditions. Electrophoretic characteristics and enzymic susceptibility of the density-gradient fractions revealed that the glycosaminoglycans constituting the proteoglycan complexes in this indigestible materials were mainly dermatan sulfate in the top three fractions, and dermatan sulfate and chondroitin sulfates in the bottom fraction; a minor constituent which was common to all the fractions was hyaluronic acid. A gel-like substance (Fr. Ig) at the top of the gradient, amounting to about 25% of the loaded dry sample, contained only a trace of hydroxyproline (less than 1%) and was composed of proteodermatan sulfate, glycoprotein, and a small amount of hyaluronic acid. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analyses of Fr. Ig with 2-mercaptoethanol showed that the major part of the proteins in this gel-like substance was cross-linked by disulfide bridges. Chromatography of Fr. Ig on Sepharose 4B in buffered 4 M guanidinium chloride containing 2-mercaptoethanol, together with the electrophoretic patterns of the resulting fractions, suggested that proteodermatan sulfate was not associated with hyaluronic acid through covalent bonds. The amino acid composition of Fr. Ig was very similar to that reported in the literature for "dermatan sulfate-protein complex", and "structural glycoprotein" or "acidic structural protein".
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PMID:Proteoglycan complexes from bovine heart valve. Fractionation by density-gradient centrifugation and gel filtration under dissociative conditions. 18 67

Explants from rabbit aortic media were incubated in MEM medium supplemented with 14C-lysine and with 10 p. 100 hyperlipemic (type IV and V) or normal human serum respectively. The incubated fragments were extracted at increasing ionic strength. The insoluble collagen and elastin were hydrolysed with collagenase and alcoholic potassium hydroxyde respectively. The radioactivity was determined in the extracts and the radioactive labelling profile of proteins was investigated on polyacrylamide gel electrophoresis in SDS. With the exception of the collagenase extract (polymeric collagen) the incorporation of the radioactivity into insoluble collagen is not altered or increases. These the incubation was carried out in the presence of hyperlipemic serum. Incorporation of the radioactivity into insoluble collagen seems not to be altered. These results show a decreased protein synthesis with a relative increase in the biosynthesis of polymeric insoluble collagen in the aortic media incubated in the presence of hyperlipemic serum.
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PMID:Action of human hyperlipemic sera on the biosynthesis of intercellular matrix macromolecules in aorta organ cultures. 18 73

Cell-free extracts from the HTl clone of cultured Chinese hamster lung cells efficiently promote the incorporation of proline into newly synthesized material, 50% of which is digestible to small peptides by highly purified bacterial collagenase. The synthesis of the these products occurs under optimal protein synthesis conditions and is inhibited by puromycin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the cell-free synthesized material reveals a major collagenase sensitive peak (20% of the total product) at mol wt 165 000 which is reflected by a collagenase sensitive material of similar size in the culture medium. Two additional collagenase digestible species (mol wt 95000 and 65000), each having a corresponding secreted product, are generated by the cell-free system. These results are consistent with the concept that procollagen is formed by the association of three individually translated pro alphachains. The data further constitute the report of a highly active homologous cell-free system capable of pro alpha chain biosynthesis derived from a cultured cell line that is a practical source for pro alphachain biosynthesis derived from a cultured cell line that is a practical source for proalpha chain mRNA as well as a unique system for elucidating regulatory mechanisms involved in collagen biosynthesis.
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PMID:Collagen biosynthesis by cultured Chinese hamster lung cells. Cell-free synthesis of procollagen alpha chains. 20 30

The uptake of latex by fibroblasts in confluent primary culture results in the secretion of collagenase at a linear rate for a prolonged period. Phagocytosis might therefore constitute an important level of collagenase regulation in corneal ulceration. The collagenase in cell cultures is present in a latent form (40,000 MW) like that obtained from organ cultures of ulcerating corneas and can be activated proteolytically. Production of the latent collagenase in cell culture depends upon the presence of serum and diminishes greatly when serum is removed from the medium. Collagenase activity can be demonstrated after the latent collagenase has been separated from serum antiproteases in the media. Alternatively, careful titration of the crude media with trypsin to saturate serum antiproteases, to release collagenase from the complex with alpha 2-macroglobulin, and to activate latent collagenase also results in measurable collagenase activity. The collagenase that is secreted cleaves fibrillar type I collagen and cleaves soluble type I collagen into the typical 3/4 and 1/4 length fragments, as demonstrated by SDS-gel electrophoresis and electron microscopy.
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PMID:Collagenase from corneal cell cultures and its modulation by phagocytosis. 22 35

The present report describes high yield enzymatic radio-iodination of the apical and basal-lateral plasma membranes of toad bladder epithelium, by a procedure that does not breach the functional integrity of the epithelium, as assessed by the basal and vasopressin-sensitive short-circuit current (SCC). Restriction of the label to the membrane surface, was ascertained by light and electron-microscopic autoradiographs. On the apical surface, the grains were over the glycocalyx and the plasma membrane. Analysis of the labeled glycocalyx by agarose gel filtration, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), as well as enzymatic and pH-dependent hydrolysis indicated that the glycocalyx is a trichloro-acetic acid-soluble macromolecular complex of high molecular weight composed of a peptide moiety attached to large prosthetic groups (presumably carbohydrates) by O-glycosidic bonds. Analysis of the labeled apical plasma membrane components by agarose gel filtration and SDS-PAGE disclosed the presence of six major species of apparent molecular weights: 23,000, 28,000, 37,000, 44,000, 68,000, and 95,000. More than half of the membrane-associated radio-iodine was in two bands of molecular weights 37,000 and 44,000. Concentrations of vasopressin and cyclic AMP sufficient to increase the SCC significantly did not modify the extent of membrane labeling or the distribution of the label among the apical membrane components (presumably proteins) as assessed by SDS-PAGE. Iodination in the presence of amiloride inhibited incorporation but did not change the pattern of the distribution of the label among the components resolved by SDS-PAGE. Iodination of basal-lateral plasma membranes, at a yield comparable to that obtained with apical labeling, was attained after about 30 min of exposure of the intact bladder to the labeling solutions. Approximately 25% of the basal-lateral labeling was lost when the epithelial cells were harvested after collagenase treatment, implying that some iodination of the basement membrane had taken place. Less than 10% of iodination of the apical or basal-lateral surfaces was accounted for by lipid-labeling. Analysis of the labeled apical and basal-lateral species by enzymatic digestion and thin layer chromatography disclosed that virtually all the radioactivity was present as mono-iodotyrosine (MIT).
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PMID:Radio-iodination of plasma membranes of toad bladder epithelium. 37 44

The extraction of isolated vertebrate smooth muscle cells at high and low ionic strength yields cell ghosts which are seen in the electron microscope to be composed of a complex network of 10-nm filaments, together with residual actin. After SDS-gel electrophoresis of the cell ghosts only 2 bands may be recognized, one corresponding to actin and the other migrating at about 55 000 mol. wt that arises from the 10-nm filaments. The 10-nm filaments are extremely sensitive to proteolysis and are absent from cells exposed to crude collagenase in the presence of Triton X-100. Such cells, lacking 10-nm filaments, still contract in response to ATP. The data indicate that the 10-nm filaments are not essential for contraction, but rather form a specialized intracellular cytoskeleton. While completely insoluble in concentrated salt solutions the 55 000 mol. wt protein is readily extracted with acetic acid from homogenized and salt-extracted smooth muscle residue. The extracted protein reassembles, on dialysis, into filaments of about 10-nm diameter and has an amino acid composition almost identical to that deduced for vertebrate neurofilaments. From the cytoskeletal role that the 10-nm filaments play in smooth muscle and, as appears likely, in other cell types the filament protein has been tentatively termed 'skeletin'. Results relating to the proportion of skeletin in smooth muscle and the structure of the 10-nm filaments are described and discussed.
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PMID:Studies on the function and composition of the 10-NM(100-A) filaments of vertebrate smooth muscle. 56 Oct 84

Collagen synthesis was studied in monolayer cultures of rabbit corneal endothelial cells by following [14C]proline and [3H]glucosamine or [3H]fucose incorporation into a fraction enriched for collagen and its precursor molecules. Sodium dodecyl sulfate gel electrophoresis of this fraction showed that it consisted of a high-molecular-weight (greater than 300,000 daltons) polypeptide. This component was collagenase sensitive and, in the presence of dithiothreitol, gave rise to two polypeptides of the apparent molecular weights of 200,000 and 160,000 daltons. Pepsin digestion of this material destroyed all the high-molecular-weight material and gave rise to a single collagenase-sensitive component of an apparent molecular weight of 115,000 daltons. This 115,000 dalton material is similar to previously observed basement membrane collagens, and the 160,000 and 200,000 dalton components are probably precursor chains of basement membrane collagen. The very-high-molecular-weight material (greater than 300,000 daltons) may represent a disulfide-linked complex of these precursor chains. DEAE-cellulose column chromatography confirmed the presence of a single procollagen species distinct from the collagen fraction. Amino acid analysis of collagen and procollagen fractions showed a decreased hydroxyproline value as compared with previously reported basement membrane collagens or collagen precursors.
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PMID:Biochemical characterization of procollagen-collagen synthesized by rabbit corneal endothelial cells in culture. 75 87


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