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)

Dacron arterial prostheses, treated or not with biopolymers (gelatin, glycosaminoglycans) were implanted in the abdominal aorta of dogs and the connective tissue synthetised inside and outside the prosthesis was studied. After 3 and 9 months of implantation the prosthesis, a joining portion and a piece of aorta were excised and put in organ culture with 14C-lysine for 3 days. Representative macromolecular extracts were then obtained by a "chemical dissection" procedure. The radioactivity and the chemical composition of these extracts was studied. The DNA content of the prosthesis was higher than that of the adjacent aorta showing a dense cellular repopulation of the prosthesis. This was confirmed by histology also which revealed the presence of a newly formed limiting elastic membrane and the presence of numerous elastic fibrils. Collagen, elastin and glycosaminoglycans could be detected in the macromolecular extracts showing that the cells which repopulated the prosthesis expressed a complete biosynthetic capacity as far as matrix macromolecules are concerned. The distribution of proteins in the extracts was as follows: 4% of total proteins were extracted in a 1M CaCl2-buffer 80% of total proteins in the collagenase extracts, 10% in the 6M urea extract. Only 0,2% of proteins were in the final elastase extract, 10 times less than in the joining aorta fragment. The proportion of the other proteins was similar in aorta and in the prosthesis as well as the chemical composition (hexosamine and hydroxyproline content) of the extracts. The proportion of collagenase-extractable proteins decreased with the time of implantation (from 3 to 9 months) and the proportion of urea-extractable proteins increased. This type of modification is similar to that found in aging aorta wall. 14C-lysine was actively incorporated in all macromolecular fractions studied. The incorporation pattern of the prothesis tissue was similar to that found for the joining host aorta, showing a similar regulatory tendency for matrix macromolecules. It appears therefore that a valid hemocompatible vascular type of connective tissue can be synthesised on the dacron arterial prosthesis and nature of this connective tissue can be influenced by previous biopolymer treatment of the synthetic prosthesis. The described procedure (incorporation of labelled precursors in organ culture) appears to be a valid method for the exploration of the regulatory processes underlying the synthetic capacity for matrix macromolecules of the newly formed tissue in the synthetic prosthesis.
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PMID:Biochemical studies on dacron arterial prostheses. 13 20

The collagen from the cuticle of Ascaris lumbricoides was digested by Clostridium histolyticum collagenase [EC 3.4.24.3] in the presence and absence of CaCl2. About 1.2 mumoles of amino groups per mg collagen was liberated when the digestion was performed in the presence of 5 mM CaCl2, whereas about 0.5 mumole of amino groups per mg collagen was liberated by digestion in the absence of CaCl2. In contrast, CaCl2 influenced the extent of hydrolysis of rat tail tendon collagen only slightly. The results suggest that CaCl2 is necessary for the hydrolysis of certain regions in the molecule of Ascaris collagen and that such structures may not be present in mammalian collagens.
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PMID:Action of bacterial collagenase on Ascaris cuticle collagen. 17 53

The influence of a 1M CaCl2 extract and of a collagenase digest of corneal stroma of the biosynthesis of the macromolecules of corneal stroma was investigated. Calf corneas were incubated "in vitro" with radioactive tracers (14C-L-proline; 3H-D-glucosamine or 35SO4) in the presence or absence of the above extracts. After incubation the corneas are submitted to a fractional extraction in order to separate the major macromolecular fractions of the stroma. An increase in incorporation of all tracers is observed in the 1M CaCl2 (CTC), TCA and urea-extracts (containing resp. the diffusible macromolecules, proteoglycans, polymeric collagen and structural glycoproteins) in the presence of the macromolecular extracts and also with the collagenase-hydrolysate of cornea. These results show the existence of a stimulation of the biosynthesis of intracellular matrix macromolecules of the cornea by corneal extracts, probably through positive "feedback" type of mechanism.
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PMID:[Regulation of the biosynthesis of macromolecules of the intercellular corneal matrix]. 17 27

The enzymatic behavior and inhibition patterns of collagenase of Clostridium histolyticum in the presence of 0.5 M and 3.4 mM CaCl2 have been examined viscosimetrically. The more concentrated salt was found to enhance the rate of digestion of calfskin collagen when either measured viscosimetrically or colorimetrically by trinitrobenzenesulfonate. However, the rate of digestion of calfskin gelatin is unaffected by 0.5 M CaCl2 as determined colorimetrically. Calcium chloride also proved to have a marked effect on the inhibitory behavior of a series of imidazole compounds. Histidine (10mM) is about three-fold more effective as an inhibitor in 0.5 M CaCl2 than in 3.4 mM CaCl2, whereas a reverse effect is true for histamine, Imidazolylpropionate (10mM) was only weakly inhibitory (16%) in 0.5 M CaCl2 and not at all in 3.4 mM CaCl2. Inhibition by 10 mM imidazole was not detectable. These observations may be useful in the design of inhibitors for tissue collagenases which share a number of common characteristics with the bacterial enzyme.
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PMID:The effect of calcium chloride on the activity and inhibition of bacterial collagenase. 17 15

The binding of Ca2+ to a previously described phosphoprotein from human parotid saliva, protein A [Bennick (1975) Biochem J. 145, 557-567] was studied by means of equilibrium dialysis. In 5 mM-Tris/HC1 buffer, pH7.5, protein A bound 664nmol of Ca/mg of protein. Km was determined to be 181 muM and the binding of Ca2+ to the protein was non-co-operative. The binding of Ca2+ apparently occurs to side-chain carboxyl groups in the protein, but protein phosphate is of minor if any importance in calcium binding. Hydrolysis of protein A by trypsin and collagenase or heating of the protein at 60 degrees or 100 degrees C did not affect Ca2+ binding. The Ca2+ binding decreases with increased concentration of the dialysis buffer and on the addition of SrCl2, or MgCl2 or MnCl2 to the dialysis buffer. Protein A does not aggregate in the presence of Ca2+, since the s20,w was identical when determined in the presence (1.30S) and absence (1.35S) of CaCl2. By use of a specific antiserum to protein A it was found that protein C [Bennick & Connell (1971) Biochem. J. 123, 455-464] and perhaps minor related components cross-reacted with protein A. No other salivary proteins showed immunological similarity. Proteins A and C were also present in submandibular saliva. The possible functions of protein A are discussed.
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PMID:The binding of calcium to a salivary phosphoprotein, protein A, common to human parotid and submandibular secretions. 18 Sep 80

The alteration of the structural organization of dermal connective tissue was studied by light and electron microscopy and by biochemical techniques in normal human and in diabetic patients using skin biopsies. Part of the tissue was used for light and electron microscopy, the rest was incubated in the presence of 3H-lysine for four hours. The 3H-lysine labelled biopsies were submitted to a sequential extraction procedure in order to obtain representative macromolecular fractions containing the matrix macromolecules. The extracts were analyzed for their chemical composition and radioactivity. Electron microscopy revealed ultrastructural modifications of the fibroblasts, of the collagen and elastic fibers in the diabetic dermis. Fibroblasts contained an increased amount of electron dense deposits in the cytoplasm and dilated endoplasmic reticulum. The collagen bundles were dissociated. Elastic fibers under the epithelial basal laminae were fragmented or absent. The incorporation pattern of 3H-lysine into these macromolecular fractions was different in the normal and diabetic skin biopsies. The percentage of total radioactivity incorporated increased significantly in the 1M CaCl2 extractable fraction an in the 6M urea extractable fraction and decreased significantly in the collagenase and elastase extracts in diabetic skin biopsy. These results demonstrate the existence of morphological and biochemical alterations in diabetic connective tissue (dermis) reflecting alterations in the relative rates of synthesis and/or degradation of the intercellular matrix macromolecules as well as of their microarchitectural arrangement.
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PMID:[Structural and biochemical alterations of human diabetic dermis studied by H-lysine incorporation and microscopy]. 18 19

Collagenase (EC 3.4.24.3) activity can be measured directly in homogenates of the involuting rat uterus. Latent forms of collagenase are activated by a brief exposure to trypsin; trypsin activity is then blocked with soybean trypsin inhibitor. Homogenizing conditions have been developed that permit 90-95% recovery of the total active and latent collagenase activity in a 6000 X g pellet, where it is presumably bound to its collagen substrate. This insoluble activity can then be extracted by heating to 60 degrees C for 4 min in 0.04 M Tris - HCl buffer, pH 7.5, containing 0.1 M CaCl2. Methods are presented for the estimation of the recovery of collagenase in the extracts; this approximates 65-70% of the total. Small amounts of activity can also be extracted from rat liver and kidney. This extraction procedure should be of use in purifying collagenase without culturing the enzyme-producing tissue and in the direct assay of tissue collagenase activity. The activity extracted from rat uterus has been proven to be collagenase by its characteristic pattern of collagen breakdown products on disc electrophoresis and by the split of tropocollagen at interband 41 as shown by electron microscopy of reconstituted fragments. The activity is inhibited by EDTA, and this inhibition is not reversed by calcium or zinc ions.
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PMID:Extraction of collagenase from the involuting rat uterus. 18 74

1. The involuting rat uterus displays an extremely rapid breakdown of collagen. Collagenase activity can be assayed directly in the insoluble 6000g pellet of uterine homogenates. At 1 day post partum, about 85% of this collagenase activity is in a latent form. 2. This latent form can be activated by trypsin or by a serine proteinase present in the uterine pellets. 3. The activating enzyme of the tissue is inhibited by a wide spectrum of trypsin inhibitors, including Trasylol, soya-bean and lima-bean trypsin inhibitors, snail inhibitor and di-isopropyl phosphoro-fluoridate. Partial inhibition is produced by benzamidine, phenylmethanesulphonyl fluoride, epsilon-aminohexanoate, leupeptin, antipain and alpha1-antitrypsin. Ovomucoid, 7-amino-1-chloro-3-tosylamido-1-heptan-2-one and 1-chloro-4-phenyl-3-(N-benzyloxy-carbonyl)amino-L-butan-2-one are not inhibitory. 4. Extraction of uterine pellets with 0.1 M-CaCl2 at 60 degrees C releases both latent and active collagenase. Exclusion chromatography on Sephadex G-100 gives an apparent molecular weight of approx. 77000 for the latent form and 66000 for the active form. The latent form is suggested to be a zymogen of collagenase.
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PMID:A latent form of collagenase in the involuting rat uterus and its activation by a serine proteinase. 19 99

Native cuticle collagen, obtained from Nereis virens, was incubated with purified bacterial collagenase (EC 3.4.4.19). The kinetics of proteolysis were monitored by viscometry, in parallel with similar digestions of calf skin collagen. Comparison of the kinetics of digestion of the two collagens, at similar enzyme to substrate ratios (w/w), showed that the native cuticle collagen was relatively refractory to digestion by bacterial collagenase. Characterization of the cuticle collagen digest by sodium dodecyl sulfate-polyacrylamide electrophoresis and agarose gel filtration in CaCl2 showed a large polypeptide, of about 300,000 daltons, to be a major product. The native form of this product, a unique fragment, was isolated from the digest by ethanol precipitation. It was found to have an intrinsic viscosity of 120 dl/g, to have an optical rotary dispersion curve characteristic of collagen, to undergo a typical collagenous thermal transition with a Tm of 23.2 degrees, and to have a calculated molar mass of 900,000 g with molecular dimensions of 9,000 X 13 A. It had an amino acid composition which was similar, but not identical with the native cuticle collagen. Although the original substrate contained two dissimilar chains, A and B, in a molar ratio of 1:2, the collagenase-resistant product appeared to be composed of only one type of polypeptide fragment. Possibly, the original subunits contain similar, if not identical collagenase-resistant regions.
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PMID:Nereis cuticle collagen. Isolation and properties of a large fragment resistant to proteolysis by bacterial collagenase. 19 99

Rat cardiac muscle was dissociated into single cells by a coronary perfusion technique with collagenase and hyaluronidase in a Ca-free medium. Retention of the cylindrical shape of isolated muscle cells could be achieved by regulation of [Ca2+]0 and temperature. Cells kept at 4 degrees C, and 0-01 mM CaCl2 remained cylindrical for more than a week and contracted spontaneously upon warming at 37 degrees C. At [Ca2+]0 between 0-1-2 mM and 37 degrees C, cells underwent contracture and rounded up. Scanning (SEM) and transmission electron microscopy were used to analyze the structure of cylindrical and rounded muscle cells. The extracellular aspect of the sarcolemma at lateral cell surfaces and intercalated disc regions were clearly revealed for SEM analysis. Both the distribution and number of T-tubule openings on the surfaces can be estimated and a three-dimensional description of the intercalated disc obtained. This study reveals that isolated adult heart cells are extremely sensitive to [Ca2+]0, but with careful control of this cation, this preparation should be helpful in the analysis of both sarcolemmal structure and the pathological changes which accompany myocardial injury.
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PMID:Studies of isolated adult rat heart cells: the surface morphology and the influence of extracellular calcium ion concentration on cellular viability. 20 Oct 46


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