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

This study describes the isolation of arylsulfatases A and B (arylsulfate sulfohydrolase EC 3.1.6.1) from human articular cartilage. These enzymes were extracted from collagenase digests of tissue homogenates. After fractionation with ammonium sulfate the enzymes were separated from each other by DEAE-cellulose chromatography and further purified by gel filtration on Sephadex G-200. Sulfatase B, subsequently chromatographed on CM-cellulose was apparently homogenous as judged by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. The enzyme has a pH optimum of 5.6, a molecular weight of 51,000 and Km of 2.6 mM for 4-nitrocatechol sulfate. Sulfatase A was found to be a glycoprotein with a pH optimum of 4.8, a molecular weight of 105,000 and a Km of 0.16 mM for 4-nitrocatechol sulfate. The competitive inhibition of both enzymes by inorganic sulfate, sulfite and phosphate support the likelihood of a common reaction mechanism. In contrast to sulfatase B which showed minimal inhibition, sulfatase A was totally inhibited by 5 mM N-ethylmaleimide.
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PMID:Enzymes from human articular cartilage: isolation of arylsulfatase B and its comparison with arylsulfatase A. 1 Oct 79

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

Mycobacterium ulcerans produces an exotoxin in culture which, when inoculated into guinea pig skin, causes inflammation, necrosis, edema, and other histopathological changes resembling those in infections of humans. The toxin was resistant to heat and to alkalies and was moderately acid labile. Toxic activity was destroyed by Pronase, phospholipase, lipase, amylase, and glucosidase but not by trypsin, collagenase, cellulase, lysozyme, hyaluronidase, or neuraminidase. Toxic activity was resistant to treatment with 2-mercaptoethanol, urea, guanidine hydrochloride, p-chloromercuribenzoate, ethylenediaminetetraacetate, and sodium deoxycholate but was destroyed by sodium m-periodate and sodium dodecyl sulfate. The toxin was precipitated by a wide range of ammonium sulfate concentrations. Extraction with chlorofrom-methanol or petroleum ether destroyed its activity. Isopycnic density gradient ultracentrifugation in KBr produced a high-density lipoprotein layer with a 24-fold increase in specific activity. The results indicate that this toxin is a high-molecular-weight phospholipoprotein-polysaccharide complex.
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PMID:Further characterization of Mycobacterium ulcerans toxin. 3 Jun 94

Seventy-five pregnant women in the 38th to 41st weeks of gestation were given a single intravenous injection of 200 mg of dehydroepiandrosterone sulfate (DHAS). The changes in estriol, 17beta-estradiol and progesterone levels in the serum, the uterine cervix and the myometrium of the placenta-implanting site were then determined. Estriol levels remained unchanged both in serum and tissue, but the level of 17beta-estradiol increased sharply both in serum and tissue after four hours. The increases of 17beta-estradiol in the serum and the portio vaginalis of the same patient were well correlated (r = 0.79898), but the percentage of increase was much higher in the portio vaginalis than in the serum (p less than 0.001). Serum progesterone levels did not change initially, but always decreased within four or eight hours in cases in which labor had started or delivery was accomplished within 24 hours (p less than 0.01 at four hours). The total amount of collagenase was determined in ten subjects before and after the administration of DHAS. The total collagenase activity was elevated by an average of 152.3%. The peak of activity was accelerated from the fourth to the second day (p less than 0.001) of the culture. A probable mechanism of DHAS action in accelerating cervical ripening is presented.
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PMID:Collagenolytic activity and steroid levels after administration of dehydroepiandrosterone sulfate. 3 88

Isolated human glomeruli were digested with purified bacterial collagenase yielding epithelial cells. These cells grew to saturation density and did not become multi-layered. They were identified as visceral glomerular epithelial cells by their morphologic appearance by phase and electron microscopy and by the presence of surface receptors for C3b. Neither Factor VIII antigen nor Fc receptors were observed. The glomerular epithelial cells synthesized a collagenous protein that was antigenically similar to human glomerular basal lamina. Proteins precipitated from visceral epithelial cell medium with affinity purified antibody against noncollagenous glomerular basal lamina antigens yielded a single collagenase labile protein that by sodium dodecyl sulfate/polyacrylamide gel electrophoresis migrated with an apparent Mr of 168,000 in the presence of reducing agents. Analysis of hydroxyproline isomers yielded a ratio of 3-hydroxyproline to total hydroxyproline of 0.17. Pepsin digestion yielded a disulfide-bonded multimer which, with reduction, migrated with an apparent Mr of 148,000. These data demonstrate that human glomerular visceral epithelial cells can be isolated and propagated in vitro and that they synthesize a collagen similar to that found in vivo.
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PMID:Human glomerular visceral epithelial cells synthesize a basal lamina collagen in vitro. 9 Nov 67

The ultrastructural identification and characterization of lung proteoglycans was studied using the polycationic dye, ruthenium red. Treating lung parenchyma with the detergent Triton X-100 increased epithelial permeability and allowed the dye to penetrate alveolar walls and stain the alveolar basement membrane and lung collagen. Ruthenium red stained numerous 10- to 40-nm granules concentrated at the lamina surface of basement membrane and attached to the major doublet collagen band. The granules attached to collagen were digested by chondroitinase ABC and papain, indicating that they represent proteoglycan aggregates containing chondroitin or dermatan sulfate. Granules observed on the alveolar basement membrane were resistant to digestion by collagenase and by all glycosidases, suggesting that heparin or heparan sulfate is the predominant glycosaminoglycan in epithelial basement membrane. Ruthenium red in association with tannic acid also stained a fine network of 3- to 10-nm filaments in which collagen was enmeshed, forming the interfibrillar matrix. This network was resistant to collagenase and glycosidase digestion but was removed after papain digestion, suggesting that it was a protein or glycoprotein that did not contain glycosaminoglycans. These methods have allowed visualization of lung proteoglycans and have identified a structure that does not contain glycosaminoglycan that is intimately associated with collagen. This technique can now be applied to explore the potential role of proteoglycans in lung development and in restructuring the lung in various disease states.
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PMID:Ultrastructural localization and characterization of proteoglycans in the pulmonary alveolus. 9 9

An enzyme which catalyzes the deamidation of thyroliberin (TRF; less than Glu-His-Pro-NH2) has been purified 110-fold from extracts of bovine anterior pituitary by ammonium sulfate fractionation, ion exchange chromatography on DEAE-cellulose, and gel filtration. This enzyme of 76,000 molecular weight (as estimated by gel filtration) exhibits maximal activity at neutral pH (optimum pH 7.4 to 7.6) in buffers of high ionic strength supplemented with thiol-protecting agents. As indicated by the strong inhibition of the enzymatic activity by N-ethylmaleimide and Hg2+, as well as by the extreme sensitivity toward diisopropyl fluorophosphate, -SH, and -OH residues apparently represent essential functional groups of the enzyme. The stereospecific deamidation of TRF (Km = 4.1 . 10(-4) M) is inhibited competitively by TRF analogues which contain proline or by the proline containing biologically active peptides luliberin (LH-RF), oxytocin, vasopressin, angiotensin II, and Substance P. TRF analogues without proline or peptide amides without proline are ineffective. This enzyme cleaves the appropriate Pro-X bonds in luliberin, angiotensin II, pyroGlu-His-Pro-Gly-NH2, and the collagenase substrate Z-Gly-Pro-Leu-Gly-Pro. Thus, it may be characterized as a post-proline-cleaving enzyme.
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PMID:Characterization of "thyroliberin-deamidating enzyme" as a post-proline-cleaving enzyme. Partial purification and enzyme-chemical analysis of the enzyme from anterior pituitary tissue. 11 64

The influence of the mode of preparation upon some of the characteristics of white adipose tissue plasma membranes and microsomes has been reported. Plasma membrane fractions prepared from mitochondrial pellet were shown to have higher specific activities of (Mg2+ + Na+ + K+)-ATPase than plasma membranes originating in crude microsomes. Isolation of fat cells by collagenase treatment was found to result in a decrease in specific activity of the plasma membrane enzymes; in plasma membranes prepared from isolated fat cells, the specific activity values obtained for (Mg2+ + Na+ +k+)-ATPase and 5'-nucleotidase were only 42% and 6.3% respectively of those obtained in plasma membranes prepared from whole adipose tissue. Purification of whole adipose tissue crude microsomes by hypotonic treatment caused extensive solubilization of the endoplasmic reticulum marker enzymes, NADH oxidase and NADPH cytochrome c reductase. The lability of endoplasmic reticulum marker enzymes, however, was found to be greatly diminished in the preparations from isolated fat cells. The possibility that NADH oxidase and NADPH cytochrome c reductase activities found in the plasma membranes are microsomal enzymes adsorbed by the plasma membranes is discussed. The peptide patterns as well as the NADH oxidase and NADPH cytochrome c reductase activity patterns of plasma membranes and purified microsomes were compared by means of sodium dodecyl sulfate or Triton X-100 polyacrylamide gel electrophoresis.
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PMID:Comparison of plasma membranes and endoplasmic reticulum fractions obtained from whole white adipose tissue and isolated adipocytes. 12 89

To investigate the dystrophic influence on the characteristics of actin, a method for the isolation of F-actin filaments from the skeletal muscle of small sizes, i.e., less than 0.5 g, was devised. In this method, minced muscle was treated with collagenase and hyaluronidase, and the isolated filaments were washed with adenosine triphosphate (ATP). Upon examination in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the ATP-washed filaments showed a protein component identical in mobility to actin in untreated myofibrils or to that prepared by the conventional method. Electron microscopic appearances of the filaments were similar to those of F-actin filaments described in the literature. The dimensions of the filaments were 0.5--2.5 micrometer in length and 60--70 A in diameter. The ability to activate the Mg-adenosine triphosphatase or myosin was found to be Ca2+ independent. In all aspects of the above characteristics, the filaments from leg muscles of 129/Re dydy dystrophic mice and their litter mates were observed to be identical.
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PMID:Isolation of F-actin filaments. Comparison of F-actin filament preparations from normal and dystrophic mouse muscle. 15 92


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