Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An inactive collagenase was harvested from both serum-free and serum-supplemented fibroblast monolayer cultures in periods of active collagen synthesis. The latent collagenase did not hydrolyze collagen and did not bind the potent collagenase inhibitor alpha2-macroglobulin. Activation with trypsin imparted to the enzyme the ability to hydrolyze collagen at neutral pH in a typical manner and to form an inhibited complex with alpha2-macroglobulin. The molecular weights, determined by calibrated gel filtration, were 78,000 and 60,000 for the latent and active enzymes, respectively. The data indicate that collagenase is released from the cells in inactive form, as a zymogen.
 ...
PMID:Synthesis and release of procollagenase by cultured fibroblasts. 5 61

Specific collagenase from the culture media of various rabbit tissues and cells exists in active and latent forms. Latent collagenase is most effectively activated with 4-aminophenylmercuric acetate, a thiol-blocking reagent, strongly suggesting that latent forms are enzyme-inhibitor complexes. A collagenase inhibitor from bone cultures, which may be closely related to the inhibitor of such latent enzyme complexes, was partially characterized.
 ...
PMID:Evidence that latent collagenases are enzyme-inhibitor complexes. 19 84

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.
 ...
PMID:Identification and partial characterization of an inhibitor of collagenase from rabbit bone. 20 52

A potent inhibitor of human collagenases, released from human tendon explants in culture, has been purified and partially characterized. The tendon inhibitor has an estimated molecular weight of 25,000. It is relatively heat-stable but undergoes loss of activity following exposure to trypsin. It inhibits trypsin-activated rheumatoid synovial collagenase as well as the enzyme obtained from polymorphonuclear leukocytes. No inhibition of collagenase from Clostridium histolyticum (clostridiopeptidase A, EC 3.4.24.3) was noted. This collagenase inhibitor may be a factor in the regulation of extracellular connective tissue catabolism.
 ...
PMID:Inhibitor of human collagenase from cultures of human tendon. 21 61

Collagenase-tissue inhibitor of metalloproteinases-1 (TIMP-1) complex was prepared from activated collagenase and TIMP-1 purified from culture media of human skin fibroblasts. After having been confirmed to be a complex by zinc chelate chromatography, the complex was demonstrated to dissociate by passage through an anti-TIMP-1 monoclonal antibody-affinity column. On the basis of above evidence, a simple strategy was set up for the independent measurements of TIMP-1 concentration, and both active and total collagenase activities in crude culture media and body fluids.
 ...
PMID:Dissociation of collagenase-tissue inhibitor of metalloproteinases-1 (TIMP-1) complex--its application for the independent measurements of TIMP-1 and collagenase activity in crude culture media and body fluids. 128 17

The levels of collagenase inhibitor, both free and bound to metalloproteinases, were evaluated at 7 days [deposit phase (DP)] and 14 days [resorptive phase (RP)] of evolution of the subcutaneous carrageenin-induced granuloma in the guinea pig. The level of free collagenase inhibitor was considerably higher in the supernatant of DP granulomas (7.95 +/- 1.53 U/mg protein) as compared to that of RP granulomas (2.53 +/- 0.41 U/mg protein). When the samples were heated at acid pH to release the inhibitor from metalloproteinase-inhibitor complexes, free inhibitor was recovered in both phases. However, the units of recovered collagenase inhibitor were several fold higher in all RP granulomas in comparison with DP granulomas (6.88 +/- 2.46 vs 1.5 +/- 0.53). Therefore, DP and RP tissues exhibited similar total amount of tissue inhibitor. By HPLC, collagenase inhibitor activity was localized in a fraction consistent with the size of TIMP. These results suggest a different balance of collagenase and collagenase inhibitor during the evolution of the granuloma; an excess of inhibitor over metalloproteinases appears to predominate during the phase of collagen accumulation contrasting with an inverse situation when the granuloma is healing.
 ...
PMID:Collagenase-inhibitory activity in deposit and resorption phases of guinea pig carrageenin granuloma. 130 44

In this report we describe the purification of bovine interstitial collagenase and provide information on its substrate specificity, kinetic parameters of catalytic activity, and amino terminal protein sequence. In addition, we present a simplified protocol for the purification of bovine tissue inhibitor of metalloproteinases (TIMP). Collagenase was purified by sequential chromatography through heparin-Sepharose, DEAE-Sepharose, and green-agarose, resulting in a product that was greater than 95% pure as judged by polyacrylamide electrophoresis. Typical of other interstitial collagenases, the isolated bovine protein was activated by protease and organomercurial treatment. It also demonstrated a kinetics and substrate specificity similar to those of human collagenase. TIMP was purified by sequential chromatography through heparin-Sepharose and DEAE-Sepharose followed by reverse-phase HPLC. The purified protein had a size, N-terminal sequence, and inhibitor activity similar to those of other mammalian TIMPs. Partial peptide sequences suggested that bovine collagenase and TIMP have strong sequence homology to their human homologues.
 ...
PMID:Purification and characterization of bovine interstitial collagenase and tissue inhibitor of metalloproteinases. 131 Nov 65

Recombinant human interstitial collagenase, an N-terminal truncated form, delta 243-450 collagenase, recombinant human stromelysin-1, and an N-terminal truncated form, delta 248-460 stromelysin, have been stably expressed in myeloma cells and purified. The truncated enzymes were similar in properties to their wild-type counterparts with respect to activation requirements and the ability to degrade casein, gelatin, and a peptide substrate, but truncated collagenase failed to cleave native collagen. Removal of the C-terminal domain from collagenase also modified its interaction with tissue inhibitor of metalloproteinases-1. Hybrid enzymes consisting of N-terminal (1-242) collagenase.C-terminal (248-460) stromelysin and N-terminal (1-233) stromelysin.C-terminal (229-450) collagenase, representing an exchange of the complete catalytic and C-terminal domains of the two enzymes, were expressed in a transient system using Chinese hamster ovary cells and purified. Both proteins showed similar activity to their N-terminal parent and neither was able to degrade collagen. Analysis of the ability of the different forms of recombinant enzyme to bind to collagen by ELISA showed that both pro and active stromelysin and N-terminal collagenase.C-terminal stromelysin bound to collagen equally well. In contrast, only the active forms of collagenase and N-terminal stromelysin.C-terminal collagenase bound well to collagen, as compared with their pro forms.
 ...
PMID:The role of the C-terminal domain in collagenase and stromelysin specificity. 131 62

1. The effects of spermine in the concentration range 0-10 mmol/l on (a) the fluid absorption, (b) the polyethylene glycol permeability, (c) the release of collagenase activity activity into the lumen and (d) the histological appearance of rat descending colon were examined. 2. Spermine (5 mmol/l) decreased fluid absorption from 48.83 +/- 2.98 (n = 7) to 23.98 +/- 2.32 (n = 6) microliters h-1 cm-2 (P < 0.01); polyethylene glycol 4000 permeability was increased from 0.030 +/- 0.001 (n = 7) to 0.047 +/- 0.003 (n = 6) cm/h (P < 0.01) and luminal collagenase activity increased from a negligible control value to 250 +/- 39 (n = 6) units/ml (P < 0.001). Spermine also caused oedema formation within the mucosal interstitial fluid, without inducing an overt breakdown of the mucosa at the luminal surface. 3. Polyamine-free dialysed seminal plasma had no effect on polyethylene glycol 4000 permeability, although it still caused a significant decrease in colonic fluid absorption from 48.83 +/- 2.98 (n = 7) (control) to 31.41 +/- 2.08 (n = 5) microliters h-1 cm-2 (P < 0.01). 4. Low-molecular-mass heparin (600 units/ml) prevented the spermine (5 mmol/l)- and whole-semen-induced increase in colonic polyethylene glycol 4000 permeability and reduced the effect of semen on fluid absorption by 63% (P < 0.001) and that of spermine by 56% (P < 0.01). 5. The Zn2+ chelator and collagenase inhibitor o-phenanthroline reduced the effect of spermine on fluid absorption and polyethylene glycol 4000 permeability by 100% (P < 0.001) and on interstitial oedema formation. o-Phenanthroline also reduced the effects of whole semen on fluid absorption (by 70%, P < 0.01) and on polyethylene glycol 4000 permeability by 95%, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Effects of spermine on water absorption, polyethylene glycol 4000 permeability and collagenase activity in rat descending colon in vivo. 133 Apr 3

We have screened six human squamous carcinoma cell lines for their ability to invade connective tissue by using the experimentally modified chorioallantoic membrane of a chick embryo as an in vivo model of invasion. In confirmation of our earlier studies, all the invasive cell lines expressed high levels of surface-bound urokinase type plasminogen activator (uPA). However, some cell lines expressing this activity were not invasive, suggesting that surface uPA, although necessary, was not sufficient. Since in addition to fibronectin, that can be degraded by uPA or plasmin, chorioallantoic membrane connective tissue contains collagen, we examined the profile of collagenases secreted by the various cell lines in search for an activity that would coincide with the invasive phenotype. We found, using gelatin substrate gels, that type IV gelatinase was produced by all six cell types tested, three cell types produced the M(r) 92,000 gelatinase, and three a lower-molecular-weight activity, which we identified by immunoprecipitation with specific antibodies, and by a direct assay of activity, as interstitial collagenase. Only the latter cells were found to be highly invasive. We showed previously that continuous culture in vitro of one of the carcinoma cell lines, HEp3, led to a gradual extinction of their malignant phenotype. To confirm the correlation between invasion and the production of interstitial collagenase, we examined these two functions in cells freshly isolated from a HEp3 tumor and intermittently during passage in vitro. We found that, although the surface uPA activity was slightly diminished in the in vitro grown cultures, it was still within the range of values found in highly malignant cells, suggesting that it is not the reason for the decrease in invasiveness. In contrast, the reduction in interstitial collagenase closely followed the loss of the invasive phenotype; after 30 in vitro passages the cells were almost completely devoid of interstitial collagenase and unable to invade. The decrease in collagenase activity was not the result of an increased tissue inhibitor of metalloproteinases production.
 ...
PMID:Invasion of connective tissue by human carcinoma cell lines: requirement for urokinase, urokinase receptor, and interstitial collagenase. 133 82


1 2 3 4 5 6 7 8 9 10 Next >>