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1.
Purification of rabbit bone inhibitor of collagenase.   总被引:20,自引:7,他引:20       下载免费PDF全文
1. Rabbit bones in tissue culture synthesize an inhibitor of collagenase during the first 4 days of culture. 2. The inhibitor was purified by a combination of gel filtration, concanavalin A--Sepharose chromatography, ion-exchange chromatography and zinc-chelate affinity chromatography. 3. The purified inhibitor migrated as a single band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and had a mol.wt. of 28000. 4. The inhibitor blocked the activity of the metalloproteinases collagenase, gelatinase, neutral proteinase III (proteoglycanase), human leucocyte collagenase and gelatinase, but not thermolysin or bacterial collagenase. The serine proteinases plasmin and trypsin were not inhibited. 5. The inhibitor interacted with purified rabbit bone collagenase with 1:1 stoichiometry. 6. The inhibitory activity was lost after incubation for 1 h at 90 degrees C, after treatment with trypsin (250 micrograms/ml) at 37 degrees C for 30 min and after reduction and alkylation.  相似文献   

2.
We have investigated the effects of altered cell shape on the regulation of the 92kDa type IV collagenase. In MDCK cells, anti-E-cadherin antibodies alter cell shape by disrupting normal cell—cell contacts, while sodium butyrate causes a marked flattening and spreading of cells. The disruption of cell—cell contacts led to a faint expression of the 92kDa collagenase. This effect was enhanced by sodium butyrate, which by itself did not induce collagenase expression. In contrast, stromelysin expression was not regulated in these conditions. Although mRNA expression was enhanced, the secreted collagenase activity was not altered in these conditions in either cell line. Examination of cytoskeletal and extracellular matrix proteins and cell—cell and cell—matrix adhesion proteins by immunofluorescence and Western blot revealed a disruption of the actin network, tight junctions, and fibronectin deposition by anti E-cadherin antibodies, and alterations in actin, cytokeratin 8, cytokeratin 14, laminin and β1 integrin induced by sodium butyrate. Thus, the induction of collagenase expression in epithelial cells by disrupted cell—cell adhesion and sodium butyrate is associated with changes in cell shape and structure.  相似文献   

3.
1. The neutral collagenase released into the culture medium by explants of human skin tissue was purified by ultrafiltration and column chromatography. The final enzyme preparation had a specific activity against thermally reconstituted collagen fibrils of 32mug of collagen degraded/min per mg of enzyme protein, representing a 266-fold increase over that of the culture medium. Electrophoresis in polyacrylamide disc gels showed it to migrate as a single protein band from which enzyme activity could be eluted. Chromatographic and polyacrylamide-gel-elution experiments provided no evidence for the existence of more than one active collagenase. 2. The molecular weight of the enzyme estimated from gel filtration and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was approx. 60000. The purified collagenase, having a pH optimum of 7.5-8.5, did not hydrolyse the synthetic collagen peptide 4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-d-Arg-OH and had no non-specific proteinase activity when examined against non-collagenous proteins. 3. It attacked undenatured collagen in solution at 25 degrees C, producing the two characteristic products TC(A)((3/4)) and TC(B)((1/4)). Collagen types I, II and III were all cleaved in a similar manner by the enzyme at 25 degrees C, but under similar conditions basement-membrane collagen appeared not to be susceptible to collagenase attack. At 37 degrees C the enzyme attacked gelatin, producing initially three-quarter and one-quarter fragments of the alpha-chains, which were degraded further at a lower rate. As judged by the release of soluble hydroxyproline peptides and electron microscopy, the purified enzyme degraded insoluble collagen derived from human skin at 37 degrees C, but at a rate much lower than that for reconstituted collagen fibrils. 4. Inhibition of the skin collagenase was obtained with EDTA, 1,10-phenanthroline, cysteine, dithiothreitol and sodium aurothiomaleate. Cartilage proteoglycans did not inhibit the enzyme. The serum proteins alpha(2)-macroglobulin and beta(1)-anti-collagenase both inhibited the enzyme, but alpha(1)-anti-trypsin did not. 5. The physicochemical and enzymic properties of the skin enzyme are discussed in relation to those of other human collagenases.  相似文献   

4.
The organ culture of neonatal mouse calvaria produced both collagenase and collagenase inhibitor. The inhibitor was purified by a series of column chromatographies: DEAE-cellulose and CM-cellulose ion-exchange chromatography, concanavalin A-Sepharose and heparin-Sepharose affinity chromatography, and finally by Sephacryl S-200 gel filtration. The purified inhibitor migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and had a molecular mass of 28,000. The inhibitor was purified 140-fold to a specific activity of 163 units/mg with a yield of 18% over the first step of the purification by DEAE-cellulose chromatography. The inhibitor stained positively for carbohydrate with periodic acid-Schiff's reagent indicating, in conjunction with its affinity to concanavalin A, that the inhibitor is a glycoprotein. In addition to mouse bone collagenase, this inhibitor also inhibited chick bone, rat bone, rabbit corneal, and human gingival collagenase, but did not inhibit bacterial collagenase.  相似文献   

5.
An inhibitor of mammalian collagenase from bovine scapular cartilage has been purified to homogeneity. The inhibitor, extracted from cartilage using 2 M NaCl, was applied to an A-1.5m gel filtration column. Inhibitor eluted at an apparent Mr of 28,000. Further purification was achieved by ion exchange chromatography, gel filtration, and reverse-phase high performance liquid chromatography. A purification of greater than 1,000-fold was achieved. The inhibitor was judged homogeneous by the appearance of a single band on a silver-stained 15% sodium dodecyl sulfate-polyacrylamide gel. Reduced inhibitor had an Mr of 27,400, unreduced inhibitor had an Mr of 23,900. NH2-terminal sequence data were obtained for the first 45 residues. The bovine cartilage-derived inhibitor exhibits greater than 65% homology over the first 23 residues with a collagenase inhibitor purified from human skin fibroblasts maintained in cell culture. This is the first demonstration that collagenase inhibitors extracted directly from tissue may be similar to those obtained from culture medium.  相似文献   

6.
A three-dimensional culture method is described in which primary pituitary adenoma cells are grown in alginate beads. Alginate is a polymer derived from brown sea algae. Briefly, the tumor tissue is cut into small pieces and submitted to an enzymatic digestion with collagenase and trypsin. Next, a cell suspension is obtained. The tumor cell suspension is mixed with 1.2% sodium alginate and dropped into a CaCl2 solution, and the alginate/cell suspension is gelled on contact with the CaCl2 to form spherical beads. The cells embedded in the alginate beads are supplied with nutrients provided by the culture media enriched with 20% FBS. Three-dimensional culture in alginate beads maintains the viability of adenoma cells for long periods of time, up to four months. Moreover, the cells can be liberated from the alginate by washing the beads with sodium citrate and seeded on glass coverslips for further immunocytochemical analyses. The use of a cell culture model allows for the fixation and visualization of the actin cytoskeleton with minimal disorganization. In summary, alginate beads provide a reliable culture system for the maintenance of pituitary adenoma cells.  相似文献   

7.
Clostridium perfringens type C NCIB 10662 produced various gelatinolytic enzymes with molecular masses ranging from approximately 120 to approximately 80 kDa. A 120-kDa gelatinolytic enzyme was present in the largest quantity in the culture supernatant, and this enzyme was purified to homogeneity on the basis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme was identified as the major collagenase of the organism, and it cleaved typical collagenase substrates such as azocoll, a synthetic substrate (4-phenylazobenzyloxy-carbonyl-Pro-Leu-Gly-Pro-D-Arg [Pz peptide]), and a type I collagen fibril. In addition, a gene (colA) encoding a 120-kDa collagenase was cloned in Escherichia coli. Nested deletions were used to define the coding region of colA, and this region was sequenced; from the nucleotide sequence, this gene encodes a protein of 1,104 amino acids (M(r), 125,966). Furthermore, from the N-terminal amino acid sequence of the purified enzyme which was found in this reading frame, the molecular mass of the mature enzyme was calculated to be 116,339 Da. Analysis of the primary structure of the gene product showed that the enzyme was produced with a stretch of 86 amino acids containing a putative signal sequence. Within this stretch was found PLGP, the amino acid sequence constituting the Pz peptide. This sequence may be implicated in self-processing of the collagenase. A consensus zinc-binding sequence (HEXXH) suggested for vertebrate Zn collagenases is present in this bacterial collagenase. Vibrio alginolyticus collagenase and Achromobacter lyticus protease I showed significant homology with the 120-kDa collagenase of C. perfringens, suggesting that these three enzymes are evolutionarily related.  相似文献   

8.
1. A specific collagenase from the culture medium of rabbit synovial fibroblasts was purified by gel filtration and ion-exchange chromatography. 2. The enzyme was homogenous on polyacrylamide-gel electrophoresis and showed only traces of contaminants when tested in gels with a non-specific antiserum. 3. The rabbit fibroblast collagenase could hydrolyse collagen both in solution and in fibrillar form. Viscometry showed that at 35 degrees C the purified enzyme could hydrolyse greater than 50 nmol of collagen/min per mg of enzyme. 4. The purified collagenase cleaved collagen in solution at either 24 degrees or 35 degrees C into the characteristic 1/4 and 3/4-length fragments. However, as compared with the impure enzyme, the purified enzyme at 35 degrees C had a much decreased capacity to further degrade the initial specific cleavage products. 5. The specific rabbit collagenase had a mol. wt. of approx. 32000 as estimated by sodium dodecyl sulphate-polyacrylamide-gel electrophoresis, and 35000 by gel filtration.  相似文献   

9.
We evaluated the possibility of deriving primary cell cultures from tissue biopsies taken in field conditions from six threaten endemic Chilean species of free-ranging mammals. Biopsies were taken either by ear punching or darts fired to animals and hold in hypothermic conditions (4 degrees C) in defined salt solution for time periods ranging from 0 to 7 d before biopsy samples reached the cell culture laboratory. Previously, holding times were evaluated in experimental cows in controlled conditions. Two enzymatic treatments, collagenase alone or collagenase followed by tripsin, were used to disaggregate tissues for cell culture. We found that ear notches and dart-derived biopsies can be storaged at 4 degrees C for 1 wk and still yield primary cultures. For dart-derived biopsies, there was an invert correlation between length of cold storage and cellular viability in culture. Healthy fibroblast cell lines were obtained in 92% of the biopsies taken despite the origin (punch or biopsy). We are not aware of similar study for free-ranging animals, especially for the use of darting system to biopsy wild terrestrial mammals, we believe that our results could help for a more widespread implementation of these procedures in the practice of ex situ conservation.  相似文献   

10.
Normal human skin fibroblast cultures have been used to assess the effects of relatively minor changes in environmental pH on collagenase, a major extracellular gene product. Collagenase accumulation in the culture medium, measured both as enzyme activity and immunoreactive material, was 2- to 10-fold greater at pH 7.6–8.2 than at pH 6.8–7.2. The pH-associated increase in collagenase was parallel by an increase in general protein synthesis. Nevertheless, prototypic lysosomal and cytoplasmic enzymes changed very little under identical culturing conditions. Although substantial intracellular protein degradation occurred at all pH values, the small differences either in general protein degradation or in specific collagenase degradation in the medium were of insufficient magnitude to account for the increased accumulation of collagenase.  相似文献   

11.
Collagenase and collagenolytic cathepsin in normal and fibrotic rat liver   总被引:2,自引:0,他引:2  
Collagenase and collagenolytic cathepsin activities in normal and carbon tetrachloride-induced fibrotic livers of rats were simultaneously determined at 35 and 25 degrees C for 18 h, using the same 14C-labeled neutral soluble collagen as a substrate. Collagenolytic cathepsin had higher activity under the assay conditions at both 35 and 25 degrees C than collagenase in normal and fibrotic livers. On sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis, the collagen was visibly degraded by collagenolytic cathepsin, but not by collagenase. These results indicate that, unlike collagenase, collagenolytic cathepsins exist as active forms in the rat liver, and can participate in the degradation of collagens, especially of soluble collagens including procollagens.  相似文献   

12.
Fragments of human, rheumatoid synovium were maintained on organ culture for three days under serum-less conditions. Their conditioned media contained collagenolytic, gelatinolytic and caseinolytic activities, which were susceptible to inhibition by lanthanide ions. Of the four lanthanides tested, Sm3+ proved the best inhibitor of gelatinase and caseinase, while La3+ inhibited collagenase the most strongly. Inhibition of collagenase by La3+ was uncompetitive. A direct binding assay confirmed the greater association between collagen fibrils and collagenase in the presence of La3+. Ca2+ was not required for binding of the uninhibited enzyme to collagen, but acted to stabilize collagenase against thermoinactivation.  相似文献   

13.
1. The neutral collagenase released into the culture medium by explants of ehrumatoid synovial tissue has been purified by ultrafiltration and column chromatography, utilising Sephadex G-200, Sephadex QAE A-50 and Sephadex G-100 superfine. 2. The final collagenase preparation had a specific activity against thermally reconstituted collagen fibrils of 312 mug collagen degraded min-1 mg enzyme protein-1, representing more than a 1000-fold increase over that of the active culture medium. 3. Electrophoresis in polyacrylamide disc-gels with and without sodium dodecyl sulphate showed the enzyme to migrate as a single protein band. Elution experiments from polyacrylamide gels and chromatography columns have provided no evidence for the existence of more than one collagenase. 4. The molecular weight of the enzyme, as determined by dodecylsulphate-polyacrylamide gel electrophoresis, was 33000. 5. Data obtained from sutdies with the ion-exchange resin and from gel electrophoresis in acid and alkaline buffer systems suggested a basically charged enzyme. 6. It did not hydrolyse the synthetic collagen peptide Pz-Pro-Leu-Gly-Pro-D-Arg and non-specific protease activity was absent. 7. The collagenase attacked undenatured collagen in solution at 25 degrees C resulting in a 58% loss of viscosity and producing the two characteristic products TCA(3/4) and TCB(1/4). 8. At 37 degrees C and pH 8.0 both reconstituted collagen fibrils and gelatin were degraded to peptides of less than 10000 molecular weight. 9. As judged by the release of soluble hydroxyproline peptides and electron microscopic appearances the enzyme degraded human insoluble collagens derived from tendon and soft juxta-articular tissues although rates of attack were less than with reconstituted fibrils. 10. The data suggests that pure rheumatoid synovial collagenase at 37 degrees C and neutral pH can degrade gelatin, reconstituted fibrils and insoluble collagens without the intervention of non-specific proteases. 11. The different susceptibilities of various collagenous substrates to collagenase attack are discussed.  相似文献   

14.
Bone explants from foetal and newborn rabbits synthesize and release a collagenase inhibitor into culture media. Inhibitor production in the early days of culture is followed first by latent collagenase and subsequently active collagenase in the culture media. A reciprocal relationship exists between the amounts of free inhibitor and latent collagenase in culture media, suggesting strongly that the inhibitor is a component of the latent form of the enzyme. Over 90% of the inhibitory activity of culture media is associated with a fraction of apparent mol.wt. 30000 when determined by gel filtration on Ultrogel AcA 44. The inhibitor blocks the action of rabbit collagenase on both reconstituted collagen fibrils and collagen in solution. It inhibits the action of either active collagenase or latent collagenase activated by 4-aminophenylmercuric acetate. Latent collagenase activated by trypsin is usually much less susceptible to inhibition. The activity of the inhibitor is destroyed by heat, by incubation with either trypsin or chymotrypsin and by 4-aminophenylmercuric acetate. Collagenase activity can be recovered from complexes of enzyme (activated with 4-aminophenylmercuric acetate) with free inhibitor by incubation with either trypsin or 4-aminophenylmercuric acetate, at concentrations similar to those that activate latent collagenase from culture media. The rabbit bone inhibitor does not affect the activity of bacterial collagenase, but blocks the action of collagenases not only from a variety of rabbit tissues but also from other mammalian species.  相似文献   

15.
The etiology of repetitive stress injuries in tendons has not been clearly identified. While minor trauma has been implicated as an inciting factor, the precise magnitude and structural level of tissue injury that initiates this degenerative cascade has not been determined. The purpose of this study was to determine if isolated tendon fibril damage could initiate an upregulation of interstitial collagenase (MMP13) mRNA and protein in tendon cells associated with the injured fibril(s). Rat tail tendon fascicles were subjected to in vitro tensile loading until isolated fibrillar damage was documented. Once fibrillar damage occurred, the tendons were immediately unloaded to 100g and maintained at that displacement for 24h under tissue culture conditions. In addition, non-injured tendon fascicles were maintained under unloaded (stress-deprived) conditions in culture for 24h to act as positive controls. In situ hybridization or immunohistochemistry was then performed to localize collagenase mRNA expression or protein synthesis, respectively. Fibrillar damage occurred at a similar stress (41.13+/-5.94MPa) and strain (13.24+/-1.94%) in the experimental tendons. In situ hybridization and immunohistochemistry demonstrated an upregulation of interstitial collagenase mRNA and protein, respectively, in only those cells associated with the damaged fibril(s). In the control (stress-deprived) specimens, collagenase mRNA expression and protein synthesis were observed throughout the fascicle. The results suggest that isolated fibrillar damage and the resultant upregulation of collagenase mRNA and protein in this damaged area occurs through a mechanobiological understimulation of tendon cells. This collagenase production may weaken the tendon and put more of the extracellular matrix at risk for further damage during subsequent loading.  相似文献   

16.
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.  相似文献   

17.
The production of collagenase by human skin explants in culture is prevented by 10(-8) M dexamethasone, 5 . 10(-4) M dibutyryl cyclic AMP, or 2.5 . 10(-3) M theophylline. Decreases in collagenase activity are paralleled by reductions in the degradation of explant collagen during the culture period. Progesterone, which effectively inhibits collagenase production in rat uterine explant cultures, has no effect on human skin explants. The inhibition by cyclic AMP is nucleotide specific. When partially inhibitory concentrations of dexamethasone and dibutyryl cyclic AMP, or dexamethasone and theophylline, are added to culture medium together, the resultant inhibition is that predicted by additivity. Synergistic inhibition, as observed in rat uterus between progesterone and dibutyryl cyclic AMP, fails to occur. Dexamethasone inhibits the production of collagenase by cultured explants of rat uterus, with complete inhibition occurring at 10(-7) M steroid. Synergism between glucocorticoids and dibutyryl cyclic AMP or between dexamethasone and progesterone could not be demonstrated in the uterine culture system. These results suggest the existence of three regulatory systems for the control of collagenase production in mammalian tissues, and that cooperativity between systems may occur on a tissue-specific basis.  相似文献   

18.
Explants of tailfin tissue from Rana pipiens or R. catesbiana undergo complete reepithelialization of the cut surfaces (healing) in culture at 22°C. After reepithelialization, these healed explants maintain normal tissue organization in subsequent culture at either 22 or 37°C. When thyroxine is added to the medium of these healed explants, an organized resorption of the tissue occurs, characterized by a gradual loss of explant size and the loss of tissue collagen which is concomitant with the appearance of collagenase in the medium. These throxine-dependent changes occur at 22°C and, more rapidly, at 37°C. Control reepithelialized explants do not resorb, lose collagen or produce collagenase. In contrast, tailfin tissue from both species, when placed in culture at 37°C directly, fails to reepithelialize and undergoes massive resorption, independent of hormonal conditions. These findings indicate that collagenase is involved in the physiological removal of collagen from the resorbing tadpole tailfin and that the expression of collagenase activity is regulated by thyroxine.  相似文献   

19.
Lens epithelial cells isolated from adult bovine were maintained in long-term culture. They synthesised important extracellular fibrils which had a similar pattern to capsule-like material in electron microscopic pictures. These fibrils were sensitive to a highly purified collagenase. After addition of labelled proline in the culture medium, the solubilized material obtained from culture preparation contained radioactive hydroxyproline. When the culture was maintained at confluency for several months, extracellular fibres with a pattern similar to fibrous long spacing collagen were observed. The collagen newly synthesised by epithelial cells has been isolated from the cells and from the medium. It has been chromatographed on agarose A5m column and analysed on sodium dodecyl sulphate polyacrylamide gel electrophoresis. Confluent lens cells were stained with anti-serum to lens capsule collagen type IV, the anti-serum stained the fibrils which are shed between the cells. Thus the collagen newly synthesised by epithelial cells has been isolated and tentatively identified as basement membrane collagen.  相似文献   

20.
The rabbit alveolar macrophage secretes at least two collagenolytic metalloproteinases in vitro including an interstitial collagenase and a type V collagenase. Using assays previously shown to discriminate between these two activities, the secretion of these two enzyme activities was investigated. Both enzyme activities accumulated in culture over 11 days and the release of both were similarly inhibited by cycloheximide. Collagenolytic activity was negligible in cell lysates. The interstitial collagenase was found in a latent form but the type V collagenase activity was active in the culture medium. When cultured in the presence of dexamethasone, the secretion of both the enzymes were identically inhibited in a dose-dependent manner. Indomethacin was an effective inhibitor of secretion of both collagenases at a concentration of 10(-5) M but not at lower concentrations. Finally, bacterial lipopolysaccharide stimulated the secretion of both type V and interstitial collagenase by these cells. These studies indicate that, like the interstitial collagenase, the type V collagenase is released from the cell as synthesized and is not stored intracellularly. Protein synthesis is necessary for the release of both these collagenases. Furthermore, the release of type V collagenase responded to dexamethasone, indomethacin, and lipopolysaccharide in a manner identical to the secretion of the interstitial collagenase suggesting that synthesis and secretion of these two enzymes are regulated in a similar manner.  相似文献   

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