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)

PZ-peptidase is an endopeptidase that cleaves the synthetic substrate developed for clostridial collagenase, 4-phenylazobenzyloxycarbonyl-L-Pro-L-Leu-Gly-L-Pro-D-Arg (PZ-peptide). The peptidase has been purified to homogeneity from chicken embryos. The enzyme has a pH optimum of 7.5 to 8.5, and isoelectric point of 5.0, and a molecular weight of 77,000. The kinetic parameters at pH 8 and 37 degrees are: Km = 2 X 10(-4) M and Vmax = 4.2 mumol/min/mg of protein. The enzyme is inhibited by p-hydroxymercuribenzoate (100%), N-ethylmaleimide (60%), and chelating agents (40 to 60%). Maximum activity is attained in the presence of reducing agents and Ca2+, Sr2+, or Mg2+. The peptidase has no detectable action on casein, serum albumin, collagen, collagen alpha chains, various collagen peptides (alpha1)(I)-CB2, alpha1(I)-CB3, alpha1(I)-CB4), (Gly-Pro-Pro)10, or (Gly-Pro-Pro)5. It does catalyze the hydrolysis of the Hyp--Gly bond in the 17-residue collagen peptide alpha1(II)-CB6-C2 and it partially digested a mixture of collagen peptides of molecular weight 350 to 2500. A role of this peptidase in collagen breakdown appears to be restricted to a late stage when degradation products would fall in the range of 5 to 30 residues.
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PMID:PZ-peptidase from chick embryos. Purification, properties, and action on collagen peptides. 1 6

The influence of the mode of preparation upon some of the characteristics of white adipose tissue plasma membranes and microsomes has been reported. Plasma membrane fractions prepared from mitochondrial pellet were shown to have higher specific activities of (Mg2+ + Na+ + K+)-ATPase than plasma membranes originating in crude microsomes. Isolation of fat cells by collagenase treatment was found to result in a decrease in specific activity of the plasma membrane enzymes; in plasma membranes prepared from isolated fat cells, the specific activity values obtained for (Mg2+ + Na+ +k+)-ATPase and 5'-nucleotidase were only 42% and 6.3% respectively of those obtained in plasma membranes prepared from whole adipose tissue. Purification of whole adipose tissue crude microsomes by hypotonic treatment caused extensive solubilization of the endoplasmic reticulum marker enzymes, NADH oxidase and NADPH cytochrome c reductase. The lability of endoplasmic reticulum marker enzymes, however, was found to be greatly diminished in the preparations from isolated fat cells. The possibility that NADH oxidase and NADPH cytochrome c reductase activities found in the plasma membranes are microsomal enzymes adsorbed by the plasma membranes is discussed. The peptide patterns as well as the NADH oxidase and NADPH cytochrome c reductase activity patterns of plasma membranes and purified microsomes were compared by means of sodium dodecyl sulfate or Triton X-100 polyacrylamide gel electrophoresis.
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PMID:Comparison of plasma membranes and endoplasmic reticulum fractions obtained from whole white adipose tissue and isolated adipocytes. 12 89

Adult rat heart cells were isolated by perfusion with a calcium-free phosphate buffer containing collagenase. Optimal conditions gave a high proportion of elongated cells. Isoprenaline increased cydic AMP content linearly, with ED50 (dose effective in 50% of the population) about 10(-7) M. Ca2+ made the cells spherical, and it nearly abolished cyclic AMP response as did lack of Mg2+.
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PMID:Cyclic AMP formation and morphology of myocardial cells isolated from adult heart: effect of Ca2+ and Mg2+. 17 47

The extracellular release from human neutrophils of the primary (azurophil) granule constituents, myeloperoxidase (MPO), chymotrypsin-like cationic protein (CCP), collagenase and lysozyme, and the secondary (specific) granule constituents, lactoferrin and lysozyme, was measured during ingestion of staphylococcus protein-A-IgG complexes. In buffer, lactoferrin release was consistently higher than that of the other protein. In serum, lactoferrin release increased concomitantly with ingestion, whereas the rate of lysozyme and especially of MPO release were stimulated to a higher degree than ingestion. Magnesium (0.5--2 mM) was more potent than calcium (0.5--2 mM) in promoting release but these cations worked synergistically. Zinc (0.5--4 mM) was found to be a potent and selective inhibitor of collagenase release. Manganese (0.25--4 mM), which inhibited the ingestion of SpA-IgG complexes, also inhibited release of CCP, collagenase, lysozyme and MPO, but actually stimulated lactoferrin release. The data suggests that lactoferrin and lysozyme may be confined to distinct granule populations or else released in a different fashion from the granules. When the effects on release of primary granule proteins are concerned it is suggested that the dissociation of binding of various agents to an anionic granule matrix may be affected differently by various cations.
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PMID:Effects of serum and cations on the selective release of granular proteins from human netrophils during phagocytosis. 22 47

Leucine-binding protein described in an earlier paper was examined to characterize the dynamic properties of the system. Leucine-binding protein assembles into a large protein polymer or complex (greater than 302,000 daltons). Colchicine reduces and Mg2+ increases the amount of polymer formed. Trypsin destroys the isolated polymer but RNAase and collagenase do not. Mg2+-ATPase activity is present in the polymer fraction. The formation of the large complex suggests a quickly adaptable structure capable of responding to ionic and environmental conditions.
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PMID:Aggregation of binding protein from rat nerve. 72 98

The attachment of rat hepatocytes to polystyrene-adsorbed serum protein is relatively insensitive to inhibitors such as dextran sulphate, cycloheximide, colchicine and cytochalasin B, and enzymes like trypsin and neuraminidase, but it is strongly dependent on divalent cations. Mg2+ supports attachment better than Ca2+, but a combination of both is required for maximal attachment. The attachment is very temperature-sensitive, with a biphasic Arrhenius plot indicating an activation energy of 123 kJ/mol above 34 degrees C and 374 kJ/mol below 34 degrees C. The adsorbed attachment-promoting serum factor is inactivated by trypsin, or by Ca2+-dependent proteases which contaminate commercial preparations of collagenase. The adsorbed factor is resistant to treatment with glutaraldehyde, neuraminidase and heating to 90 degrees C, whereas the same factor in the unadsorbed state (in serum) is destroyed by heating to 70 degrees C. The factor in serum is unable to compete with the adsorbed factor for cell binding, hence it would appear that adsorption to polystyrene induces the active, heat-resistant conformation of the factor.
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PMID:Effect of temperature and divalent cations on the substratum attachment of rat hepatocytes in vitro. 74 33

Addition of estradiol-17beta in vitro to suspensions of isolated endometrial cells resulted in significant effects on glucose, water and electrolyte metabolism. Cells were prepared from uterine tissues of ovariectomized rats. In part, the procedures involved incubation with collagenase in Ca2+-, Mg2+-free, phosphate-buffered mammalian Ringer's solution, followed by restoration of divalent cations before gentle scraping of the endometrium from the underlying smoothmuscle. Cells were then disaggregated, washed, separated from coarse and fine debris, and incubated in an enriched medium for 2 h before the start of all experiments. Cellular integrity was established by measurement of electrolyte contents and by dye exclusion methods. Substantial production of 14CO2 from glucose-U-14C by the cell suspensions provided further evidence of cell viability. Estradiol-17beta, 10-9M, elicited significant increments in sodium and water contents within 2 h. Addition of estradiol-17beta, but not the alpha-epimer, also resulted in a significant increase in the yield of 14CO2 as early as 1.5 h, peaking at 2 h. The responses were dose-dependent between 10-10M through 10-8M. The stimulatory effect of estradiol-17beta at 10-9M was abolished in the presence of 3 times 10-6M cortisol or by cellular homogenization. Epithelial cells isolated from rat urinary bladder responded significantly to 6 times 10-9M aldosterone but not to estradiol-17beta, demonstrating specificity of the target site. These data lend further support to the suggestion that a primary action of estrogen in its target cell involves specific changes in the ionic and biochemical profile of the cytoplasm which may ultimately be communicated to the nucleus.
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PMID:Steroid hormone-responsive, isolated endometrial cells. 112 Apr 83

In normal lung growth, post-pneumonectomy lung growth, and in possibly several lung disorders, there are marked alterations in the density of collagen and changes in the rate of synthesis of collagen relative to the synthesis of other lung proteins. To provide a technology to begin to understand these changes at the molecular level, polysomes were prepared from rabbit lung and translated in a heterologous cell-free system including rabbit reticulocyte 0.5 M KCl ribosomal wash fraction and liver tRNA. Collagen was shown in the cell-free product by collagenase sensitivity, hydroxylation of incorporated proline by peptidyl prolyl hydroxylase, agarose gel chromatography, and sodium dodecyl sulfate acrylamide gel electrophoresis. The cell-free system was optimized with respect to K+, Mg2+, amino acids, and ribosomal wash fraction and used under conditions where total protein synthesis and collagen synthesis are linear with respect to time and amount of polysomes. Under these conditions, collagen synthesis was directed almost entirely by polysomes derived from the endoplasmic reticulum. Polysomes isolated from late fetal lung directed collagen synthesis at twice the rate (per polysome) as those polysomes isolated from adult lung. Similar changes were seen if lung tRNA replaced liver tRNA and if lung ribosomal wash fraction replaced reticulocyte wash fraction. Although these changes in cell-free lung collagen synthesis with tissue explants, further studies will have to be carried out to determine whether, in fact, age-related alterations in control of lung collagen synthesis are truly explained by these findings.
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PMID:Characterization of cell-free synthesis of collagen by lung polysomes in a heterologous system. 116 43

A large Mg2+ cell uptake against concentration gradients is stimulated in collagenase-dispersed rat myocytes by carbachol and in hepatocytes by carbachol or vasopressin. The signalling pathway(s) responsible for this stimulation of Mg2+ uptake was investigated by using various activators or inhibitors of protein kinase C (PKC) and by correlating Mg2+ uptake with cell PKC activity and cAMP content. In both cell preparations, the direct stimulation of PKC by diacylglycerol analogs or phorbol esters reproduce the same pattern of Mg2+ uptake as that induced by carbachol or vasopressin. These data indicate that the activation of PKC is responsible for a stimulation of Mg2+ uptake by myocytes or hepatocytes, whereas increase in cAMP in these cells stimulates Mg2+ release.
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PMID:Regulation of Mg2+ uptake in isolated rat myocytes and hepatocytes by protein kinase C. 131 Feb 87

Isoproterenol increased the Mg2+ content of hepatocytes after injection into rats or after addition to collagenase-dispersed hepatocytes. cAMP also the increased cellular Mg2+ content of isolated hepatocytes. This effect was prevented by staurosporine. Phorbol ester had no effect on the Mg2+ content of isolated hepatocytes, and after injection of isoproterenol into rats, protein kinase C of liver was not affected. It was concluded that isoproterenol induced long-term Mg2+ influx via the activation of protein kinase A which can be inhibited by staurosporine.
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PMID:Isoproterenol-induced Mg2+ uptake in liver. 132 36


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