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)

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

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

An enzymatic method is described for isolating intact parenchymal cells from rat livers. 3--4 g cells (wet weight) could be isolated from livers of rats weighing 180--230 g. After an in vitro preperfusion of 15 minutes with a Ca-free buffer, collagenase (200 mg/1) and calcium chloride (5.2 mmol/1) were added. Perfusion was continued for another 15 minutes at 37 degrees C. Micromorphological integrity of cell membranes was demonstrated by scanning electron microscopy. With regard to rates of gluconeogenesis and protein synthesis, parenchymal cells isolated according to our method were found to be superior to liver slices and cells isolated by other methods. Ratios of ATP/ADP (5.69) and of lactate/pyruvate (8.64) as parameters of the energetic situation and the redox state resp. were found within the physiological range. Integrity of cell surface receptors was proved by their sensitivity to epinephrine, glucagon and insulin. Glucagon (0.3 mumol/1) and epinephrine (1 mumol/1) and reduced glycogen deposition in hepatocytes of fasted rats by 84.9 % and 95.9 % resp. Both hormones stimulated glycogenolysis in parenchymal cells of fed rats to a similar extent. Urea synthesis was stimulated 29.5 % by glucagon (1 mumol/1), and inhibited 28.0 % by insulin (10 nmol/1). The stimulatory effect of glucagon (1 mumol/1) was abolished by insulin (10 nmol/1).
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PMID:[Isolation of intact liver parenchymal cells by a modified enzymatic method]. 16 41

1. Complex carbohydrate fractions were extracted successively with 40% aqueous EDTA (pH 7.4) and 6M urea (PH 7.8) FROM ACETONE-DRIED bone powder of rabbit femur. 2. The carbohydrate fraction extracted with EDTA (E=Fr) was separated into five fractions,D1approximatelyD5 by DEAE-Dephadex A-50 column chromatography. Chemical and infrared spectral analyses, and enzymatic digestion indicate that D2 contained lessacidic glycoprotein, D3 contained sialoglycoprotein, D4 contained a low sulfated proteokeratan sulfate-like substance, and d5 contained glycoprotein-bound chondroitin sulfate A plus protein-free chondroitin sulfate A. 3. Two fractions, HU-D1 and HU-D2, were isolated from the carbohydrate fraction extracted with urea (HU-Fr) by successive digestion with collagenase [EC 3.4.99.5] and pronase, followed by gel-filtration on Sephadex G-100 and then DEAE-Sephadex A-50 column chromatography. HU-D1 and HU-D2 contained a low sulfated keratan sulfate-like substance linked to peptide and glycopeptide-bound chondroitin sulfated keratan sulfate-like substance linked to peptide and glycopeptide-bound chondroitin sulfate A, respectively. 4. The present findings indicate that rabbit femur contains low sulfated proteokeratan sulfate-like substances with varying sulfate contents and glycoprotein-bound chondroitin sulfate A as the principal glycosaminoglycans. The macromolecules bound more tightly to the tissue contain much more sulfate than the corresponding loosely bound ones.
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PMID:Glycosaminoglycans and glycoproteins isolated from rabbit femur. 16 83

An enzyme capable of digesting native collagen in solution at neutral pH was extracted from the 6 000 times g sediment of the involuting uterus of the mouse and of the back skins of mice and rats. The collagenase could be dissociated at cold-room temperature from the sediment in about equal amounts when neutral Tris buffer containing 1.0M NaCl or 5M urea was used for the extraction step. The enzyme has been concentrated by ammonium sulfate precipitation and the activity was measured by using [14C]collagen in solution at pH 7.5. Collagen breakdown products were identified by disc electrophoresis. The amount of enzyme extracted was a function of temperature and salt concentration. As 5M urea extracted collagenase from the sediment in a relatively short time, this method of extraction seems to be a useful tool for serial experiments in the study of collagenase activity in collagen-rich tissues.
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PMID:Extraction of collagenase from the 6000 times g sediment of uterine and skin tissues of mice. A comparative study. 17 Jan 81

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

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

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

Collagenolytic activity has been demonstrated in the early phase of chemical carcinogenesis of mouse skin following 3-methylcholanthrene application dropwise in acetone or painted on the skin in benzene. In addition very high levels of collagenase could be detected in mouse skin papillomas and carcinomas. In all the tissues investigated, collagenase activity was extracted from the 6000 X g sediment of tissue homogenates with 5 M urea in 50 mM Tris-HCl buffer, pH 7.5. After dialyzing the extract, the enzyme was precipitated with ammonium sulfate and the activity determined against 14C-collagen substrate in solution. This procedure was found suitable for the detection and estimation of collagenase activity in skin tissues with high turnover of collagen and thus offers an attractive alternative to tissue culture methods.
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PMID:Extractable collagenase and carcinogenesis of the mouse skin. 20 Mar 99

High amounts of collagenase were found in chemically-induced carcinomas of the mouse skin and in carcinomas of the human urinary bladder. Part of the total enzyme activity was detected in the supernatant after sedimentation of the tumour homogenate at 6000 x g and dialysis for 48 hours. The remainder was extracted from the pellet by the use of 5 M urea. Though the localization of enzyme production and regulation of enzyme activity is still unclear, the collagenases may be implicated in the breakdown of collagen structures during tumour invasion.
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PMID:[Collagenase activity in an animal and a human carcinoma (author's transl)]. 20 Nov 8


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