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)

A peptidase cleaving a synthetic substrate for collagenase, 4-phenylazobenzyloxycarbonyl-L-Pro-L-Leu-Gly-L-Pro-D-Arg (designated as PZ-peptide) has been purified extensively (about 5200-fold) from a soluble extract of monkey kidney with a view of carrying out studies on its possible physiological role. The purified PZ-peptidase appeared essentially free of collagenase, nonspecific protease and di- and tri-peptidase activities. The properties of the purified PZ-peptidase resemble very much the granuloma enzyme. It is optimally active around pH 7.0. Its apparent Km value for PZ-peptide is 0.72 mM and V is 10.1 mumol/mg protein/min. It is reversibly inhibited by p-hydroxymercuribenzoate and HgCl2, whereas iodoactetamide does not affect the enzyme activity. N-Ethylmaleimide inhibited the enzyme partially (50%). Heavy metals like Cu-2+, Cd-2+, Ag+, Pb-2+, Ni-2+, and Zn-2+ completely inhibited the enzyme activity, while the inhibition by Co-2+ was only partial. Fe-2+ did not exert any effect on the activity. The enzyme activity was completely inhibited by EDTA and was restored almost to the original value by metal ions like Mn-2+, Mg-2+, Ca-2+ and Ba-2+. The approximate molecular weight of the purified enzyme was estimated to be 56 000.
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PMID:Purification and properties of a peptidase acting on a synthetic substrate for collagenase from monkey kidney. 16 32

1. Cathepsin B, a tissue (lysosomal) proteinase, and two humoral proteinases, plasmin and kallikrein, activate the latent collagenase ('procollagenase') which is released by mouse bone explants in culture. Other lysosomal proteinases (carboxypeptidase B, cathepsin C and D) and thrombin did not activate the procollagenase. Dialysis of the culture fluids against 3M-NaSCN at 4 degrees C and, for some culture fluids, prolonged preincubation at 25 degrees C also caused the activation of procollagenase. 2. In all these cases, activation of procollagenase involved at least two successive steps: the activation of an endogenous latent activator present in the culture fluids and the activation of procollagenase itself. 3. An assay method was developed for the endogenous activator. Human serum, bovine serum albumin, casein and cysteine inhibited the endogenous activator at concentrations that did not influence the collagenase activity. N-Ethylmaleimide and 4-hydroxy-mercuribenzoate stimulated the endogenous activator, but iodoacetate had no effect. 4. It is proposed that cathepsin B, kallikrein and plasmin may play a role in the physiological activation of latent collagenase and thus initiate degradation of collagen in vivo. This may occur whatever the molecular nature of procollagenase (zymogen or enzyme-inhibitor complex) might be.
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PMID:Further studies on the activation of procollagenase, the latent precursor of bone collagenase. Effects of lysosomal cathepsin B, plasmin and kallikrein, and spontaneous activation. 19 17

This study was performed to characterize the matrix metalloproteinases (MMPs) produced during the degradation of cotton-wrapped cartilage, implanted into the murine air pouch. One, two or three weeks following cartilage implantation, proteins were extracted from the granulation tissue and MMP activities were measured. Although collagenase-, gelatinase- and stromelysin-like activities were detected at each time point, gelatinase activity was by far the most prominent. These enzymes were inhibited by EDTA, but not by NEM or PMSF, indicating that these proteinases were metalloproteinases. Gelatin zymography revealed several lysis zones amongst which a major 92-kDa band shifted to 83- and 68-kDa species during the course of implantation. The emergence of these species coincided with enhanced gelatinolytic activity and collagen loss from the implanted cartilage.
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PMID:Gelatinase is the main matrix metalloproteinase involved in granuloma-induced cartilage degradation. 133 18

In freshly collagenase-isolated rat pancreatic islets and in islets cultured for 72 hours, the effects of thiol reagents on glucagon (5 micrograms/ml) and/or glucose (16.7 mM)-mediated increases in cAMP formation as well as on clonidine (10 microM)-induced inhibition of these actions were studied. In freshly isolated islets and to a more pronounced degree in islets cultured for 72 hours glucagon (5 micrograms/ml) increased the cAMP content above the basal value. Clonidine (0.1-100 microM) had no significant effect on the basal cAMP formation, but inhibited the glucagon-mediated effect. The thiol reagents diamide (10-100 microM) and NEM affected neither the basal nor the glucagon-mediated effect, but abolished the inhibitory action of clonidine on cAMP formation. In freshly isolated islets, high glucose concentrations (8.3-16.7 mM) increased the cAMP formation. Diamide (100 microM) and NEM (100 microM) attenuated the stimulatory effect of 16.7 mM glucose. It is suggested that these selective effects of the thiol reagents on glucagon-mediated increase in cAMP formation in the presence of substimulatory concentration of glucose may be due to the differences in the sensitivity of the sulfhydryl groups of the G-proteins to thiol reagents i.e. Gi or proteins closely related to Gi being more sensitive than Gs. The data further suggest that glucose acts on the cAMP cascade at a step distinct from Rs. Since both glucose and glucagon effects were influenced by the addition of clonidine, it is possible to interpret the data as indicating that the effects of both stimulators eventually converge at some common step in the adenylate cyclase cascade.
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PMID:Thiol reagents (diamide and N-ethylmaleimide) inhibit increase in cAMP in response to glucose and abolish the clonidine-mediated attenuation of glucagon-induced cAMP formation in isolated rat pancreatic islets. 196 19