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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)
Nine cultures of fibroblast cell types and 13 epithelial-like cell types were maintained for 1 week in media supplemented with L-asborbic acid (50 microgram per ml). All fibroblast-like cultures produced extracellular fibers that stained positively by a silver-impregnation reticulin stain. Nine of the 13 epithelial-like cultures produced fibers that stained positively for reticulin. Nearly all cultures not supplemented with ascorbic acid showed no fiber staining. Those few lines that stained positively for reticulin in the absence of ascorbic-acid supplementation demonstrated only slight reticulin formation. Reticulin from one fibroblast culture and one epithelial culture was examined by electron microscopy, and the silver-impregnated fibrils were morphologically identical to
collagen
. The reticulin was digestible with
collagenase
, providing further evidence that the silver-impregnation reticulin stain identifies
collagen
in culture. The demonstartion of
collagen
can be performed easily in histology laboratories using Formalin-fixed cells, and provides a means of assaying a functional property of cells in culture which is characteristic of connective tissue fibroblasts in general as well as certain specialized epithelia.
...
PMID:Histochemical demonstration of collagen fibers in ascorbic-acid-fed cell cultures. 8 Mar 77
Three different types of neutral proteases related to
collagen
metabolism have been found in the granule fraction of human leucocytes from normal adults, using
collagen
, gelatin, and synthetic peptides as substrates. These are
collagenase
, an enzyme showing a potent hydrolytic activity against gelatin but little against native
collagen
, and one splitting the cross-links region of
collagen
. Their molecular weights were estimated to be about 75,000 150,000, and 25,000, respectively, by gel chromatography. The former two enzymes were inhibited by a alpha2-macroglobulin and ethylenediaminetetraacetate, but not by alpha1-proteinase inhibitor (alpha1-antitrypsin) or phenylmethylsulfonylfluoride, while the latter enzyme, associated in behavior with an enzyme hydrolyzing succinyl-(l-alanyl)3-p-nitroanilide, was inhibited by alpha1-proteinase inhibitor, alpha2-macroglobulin, and phenylmethylsulfonylfluoride, but not by ethylenediaminetetraacetate. A possible cooperative function of these enzymes in
collagen
catabolism is discussed.
...
PMID:Human leucocyte neutral proteases, with special reference to collagen metabolism. 8 54
Collagenase activity was studied in human leukocytes, gingival crevicular fluid and bacterial plaque, with soluble radioactive
collagen
as substrate. Inflamed gingiva liberated vertebrate type
collagenase
into the crevicular fluid in active form. Healthy gingiva, in contrast, released
collagenase
in a latent form that could be activated by trypsin or plaque. Plaque also stimulated leukocytes to release
collagenase
, and activated the latent enzyme.
...
PMID:Activation of latent collagenase of human leukocytes and gingival fluid by bacterial plaque. 8 62
Tadpole
collagenase
hydrolyzed native and denatured
collagen
and synthetic peptides with sequences of 2,4-dinitrophenyl-L-prolyl-L-leucylglycyl-L-isoleucyl-L-alanylglycyl-L-arginie amide and 2,4-dinitrophenyl-L-prolyl-L-glutaminyl-glycyl-L-isoleucyl-L-alanylglycyl-L-glutaminyl-D-arginine. The specific enzyme activity against the latter substrate and
collagen
fibrils is found to be 933 nmol/min per mg protein and 8440 units (microgram
collagen
degraded/min), respectively. Optimum pH for the enzyme is 7.5-8.5. A
collagenase
complex with alpha2-macroglobulin did not hydrolyze
collagen
fibrils, but digested the synthetic substrates at the Gly-Ile bond. The amino acid composition of the enzyme was determined. Immunoelectrophoresis of the enzyme at pH 8.6 against anti-tadpole
collagenase
rabbit immunoglobulin G shows a single precipitin line at a position migrating faster than human serum albumin and corresponding to enzyme activity against
collagen
fibril and synthetic substrates.
...
PMID:Purification of tadpole collagenase and characterization using collagen and synthetic substrates. 8 65
To assess potential abnormalities in
collagen
metabolism in systemic scleroderma, skin fibroblast lines from patients with this disease were established and compared to control cell lines derived from healthy subjects. For studies on the biosynthesis of procollagen, the cells were incubated with [(14)C]proline in a medium supplemented with ascorbic acid and beta-aminopropionitrile, and the synthesis of nondialyzable [(14)C]hydroxyproline, in relation to DNA or cell protein, was taken as an index of procollagen formation. Five of eight scleroderma fibroblast cell lines demonstrated procollagen biosynthesis rates significantly higher than the controls, and the mean rate of procollagen synthesis by scleroderma fibroblasts was about twice that of the control cells. Control experiments demonstrated that the specific activity of the intracellular free proline was not different in scleroderma and control fibroblasts, and the mean population doubling times of the scleroderma and the control fibroblast cell lines were the same. The relative synthesis of the genetically distinct procollagens was examined by isolating type I and type III procollagens from the cell culture medium using DEAE-cellulose chromatography. The ratios of type I/III procollagens in scleroderma cell lines did not differ from the controls. The helical stability of the collagenous portion of type I and type III procollagens, estimated by the resistance of (14)C-
collagen
to limited proteolytic digestion with pepsin under nondenaturing conditions, was the same in both scleroderma and control cultures. The capacity of the cells to synthesize enzymatically active and immunologically reacting
collagenase
was also studied; no marked differences in these parameters could be observed. The results suggest that cultured skin fibroblasts from patients with scleroderma demonstrate a metabolic abnormality expressed as increased synthesis of type I and type III procollagens in a normal ratio. This abnormality may play a role in the excessive accumulation of
collagen
in the skin and other organs affected in scleroderma.
...
PMID:Scleroderma: increased biosynthesis of triple-helical type I and type III procollagens associated with unaltered expression of collagenase by skin fibroblasts in culture. 9 59
A preparation rich in basement membranes isolated from rat testes (STBM) was exposed to pepsin,
collagenase
, trypsin, and pronase to obtain soluble fractions. The immunological reactivity of these fractions was studied by gel immunodiffusion or by passive hemagglutination tests against an anti-STBM serum. All fractions reacted with the antiserum, but the highest titer was detected when the antiserum was reacted with a fraction that contained only traces of hydroxyproline (fraction 1), whereas low titers were obtained with
collagen
or
collagen
fragments isolated from STBM. Antibodies in the anti-STBM serum were mainly directed to the glycoproteins of STBM not related to
collagen
. Fraction 1, obtained by subsequent
collagenase
and trypsin digestion of STBM and purification by Sephadex G-200, was a high molecular weight glycoprotein that was free of half-cystine and methionine, had only traces of hydroxyproline, and contained 7.2% neutral sugars, 0.26% sialic acid, and 8.7 residues of glucosamine per 1000 residues of amino acids.
...
PMID:Isolation and immunological reactivity of soluble fractions from rat seminiferous tubule basement membrane. 9 Apr 90
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.
...
PMID:Human glomerular visceral epithelial cells synthesize a basal lamina collagen in vitro. 9 Nov 67
Cold-insoluble globulin was detected in both trophoblast and alveolar basement membrane preparations, whereas it was not detected in GBM preparations. Acidic structural glycoproteins from both placental villi and lung parenchyma, which were extracted with 0.3 M acetic acid and recovered by adjusting the pH to 4.7, also contained CIg. Fractions of TBM, solubilized by either dilute alkali (0.01 N NaOH), by reduction and alkylation of the disulfide bonds, or by 0.3 M acetic acid extraction, all contained the antigen and possessed properties similar to those of ASG. The ASG fractions also reacted with antifibrinogen, but proof that the two types of determinants occur on a given molecular species is lacking at present. Purified
collagenase
solubilized CIg from ABM, from lung parenchyma, and from the stroma of placental villi, and this finding is strong evidence for an association of CIg with
collagen
in these connective tissues.
...
PMID:Presence of fibronectin in basement membranes and acidic structural glycoproteins from human placenta and lung. 9 37
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.
...
PMID:Ultrastructural localization and characterization of proteoglycans in the pulmonary alveolus. 9 9
Basement membrane (type IV) collagens were extracted from a mouse tumour with acetic acid and from human placenta after limited enzymatic digestion. Antisera were produced against both collagens in rabbits and guinea-pigs and examined by various assays. These antisera were found to be specific for basement membrane
collagen
and showed little or no cross-reactions with the interstitial collagens, types I, II and III or with human placenta
collagen
consisting of alpha A and alpha B chains. Varying degrees of cross-reaction were observed between antisera to human and mouse type IV
collagen
. Immunochemical analyses demonstrated the presence of three distinct determinants in the tumour type IV
collagen
. Rabbit antisera against this antigen reacted with either
collagenase
-resistant segments or with a collagenous, disulphide-bonded segment (P3). Guinea-pig antisera recognized primarily antigenic determinants in the P3 segment. Antisera to placenta type IV
collagen
reacted with another collagenous, pepsin fragment (P1) which lacks disulphide bonds. These antisera showed complete cross-reaction with collagenous alpha 1 (IV) chains prepared from pepsin-digests of human placenta and bovine lens capsule.
...
PMID:Immunochemical study on basement membrane (type IV) collagens. 9 54
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