Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

The specificity of thermomycolase toward glucagon and the oxidized A and B chains of insulin was investigated. Extensive digestion of glucagon occurred when conducted at pH 7.0 and 45 degrees C for 40 min, whereas hydrolysis of only three peptide bonds occurred at pH 7.0 and 28 degrees C for 5 min. A similar situation was observed for the oxidized B chain of insulin, which exhibited only a single major cleavage after 5 min at 25 degrees C. No well-defined specificity for particular amino acid residues was evident, but ready hydrolysis of peptide bonds occurred within sequences containing non-polar residues. This endoproteinase must therefore possess an extended hydrophobic binding site for polypeptides. Thermomycolase hydrolysed acetylalanylalanylalanine methyl ester and elastin-Congo Red at 22 and 8.5 times the rate of porcine elastase respectively. A limited degradation of native collagen and significant hydrolysis of benzyloxycarbonyl-Gly-Pro-Leu-Gly-Pro were suggestive of some collagenase-like activity. No keratinase activity was apparent.
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PMID:The substrate specificity of thermomycolase, an extracellular serine proteinase from the thermophilic fungus Malbranchea pulchella var. sulfurea. 0 73

It is apparent that significant progress has been made in our understanding of the biosynthesis, modifications, and maturation of collagen and elastin. We now recognize and partially understand special reactions involved in hydroxylations within the cell and complex cross-linking processes occurring outside the cell. Recent experiments (191) have shown that in human diploid fibroblast cultures of limited doubling potential (191) the hydroxylation of collagen prolyl residues appears to be "age" or passage-level dependent. With increasing passage level of these cultures, both the ascorbate requirements and the extent of collagen hydroxylation decrease. "Young" cell cultures have a strong requirement for complete hydroxylation and without ascorbate there is only about 50% of the normal level. "Middle-aged" cultures show higher hydroxylation without and full hydroxylation with ascorbate, whereas "old" (or cultures close to "senescence") are incapable of full hydroxylation with or without ascorbic acid. Although the overall system may show some deterioration with increasing passage levels, it appears that with increasing passage levels other components in the cell replace the ascorbate dependence of the hydroxylase system to a greater exten. In some ways, aging WI-38 cultures begin to resemble some transformed cells in their biochemical reactions, although they continue to remain diploid and eventually lose the ability to replicate. It is not yet known whether old animals can produce collagen, which may now be underhydroxylated, perhaps contributing to certain senescent changes. Careful examination of the hydroxylation index of collagen produced in organoid cultures of tissue biopsies as a function of donor age might be informative, particularly if one looks at the quality of collagen by employing collagenase and other proteolytic digests with collagen (191). One could comare the levels of frequent and characteristic peptide triplet sequences such as Gly-Pro-Hyp to Gly-Pro-Pro, Gly-Ala-Hyp to Gly-Ala-Pro, or Gly-Pro-Hyl to Gly-Pro-Lys and others for evaluation of hydroxylation throughout the entire molecule or at selected sequences.
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PMID:Posttranslational protein modifications, with special attention to collagen and elastin. 5 Jun 3

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

Human lung tissues were exposed to proteolytic enzymes to determine the effects on tensile strength and to clarify the relationship between tensile strength and the amounts of collagen and elastin in the tissue. Elastase and papain depleted the tissue of elastin but failed to alter tensile strength. Trypsin had no effect on tensile strength, or on collagen and elastin content. collagenase lowered tensile strength and reduced the amount of collagen in the tissue. The findings with collagenase were in agreement with measurements in control tissues that showed a direct relationship between tensile strength and collagen content. These results confirm collagen as the principal determinant of the tensile strength of human lung.
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PMID:The effects of proteolytic enzymes on the tensile strength of human lung. 16 67

ClostrIdium histolyticum collagenase (clostridiopeptidase A, EC 3.4.4.19) was purified by batchwise separation with DEAE-cellulose followed by affinity chromatography on a column of alkali-treated elastin. The N-terminal amino acid profile of elastin isolated from bovine ligamentum nuchae using this enzyme preparation was compared with that of a duplicate sample purified with a mixture of collagenase I and II (Yoshida, E, and Noda, H. (1965) Biochim. Biopsys. Acta 105, 562-574). An approx. three-fold decrease in the molar concentration of N-terminal residues and a considerable reduction in their number was obtained by using the former enzyme preparation.
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PMID:Application of affinity chromatography to the purification of collagenase for the isolation of insoluble elastin. 16 35

Thioglycolate-stimulated mouse peritoneal macrophages secrete a Proteinase which degrades insoluble elastin. There is little elastase activity in cell lysates but the bulk of the enzyme accumulates extracellularly during culture in serum-free medium. The secretion of elastase is sustained for over 12 days in culture and continued secretion of elastase requires protein synthesis. Unstimulated macrophages secrete very little elastase activity but can be triggered to secrete higher levels of this enzyme by phagocytosis and intracellular storage of latex particles. The macrophages elastase is a distinctive proteinase differing from the elastases of pancreas and granulocytes and is distinct from the other secreted proteinases of macrophages, namely, collagenase and plasminogen activator. The macrophages elastase is a serine proteinase and is inhibited by di-isopropyl phosphoro-fluoridate, ovoinhibitor, EDTA, dithiothretiol, and serum. Its activity is little affected by soybean trypsin inhibitor, turkey ovomucoid and chloromethyl ketones derived from tosyl lysine, tosyl phenylalanine, and acetyltetra alanine. Hydrolysis by macrophage elastase of chromogenic ester substrates for pancreatic elastase could not be detected. Elastase secretion by stimulated macrophages exceeds that by primary and established fibroblast cell strains. It is likely that elastase secretion by macrophages plays a major role in the pathogenesis of chronic destructive pulmonary diseases such as emphysema.
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PMID:Elastase secretion by stimulated macrophages. Characterization and regulation. 16 96

Clostridium histolyticum collagenase (clostridiopeptidase A, EC 3.4.4.16), purified by affinity chromatography, was applied to the isolation of insoluble elastin from bovine aorta. The extremely low level of N-terminal residues (1.6 mol per 10(6) g of protein) present in this preparation indicated the almost complete lack of hydrolytic damage caused by the isolation procedure. The amino acid profile of the aortic elastin was found to be almost identical to that of insoluble elastin prepared from bovine ligamentum nuchae by the same method.
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PMID:The application of collagenase, purified by affintiy chromatography, to the isolation of insoluble elastin from bovine aorta. 16 62

1. The contents of the fibrous proteins collagen and elastin in the pleural and parenchymal regions of bovine lungs were determined. The collagen content was approx. 70% (g/100g of salt-extracted defatted powder) in each tissue, and the elastin content was 28% in pleura and 13.5% in parenchyma. 2. Purification of the insoluble collagen from the pleura and parenchyma of bovine lungs by various methods was attempted. The collagen fractions isolated after incubation of the pulmonary tissues with the proteolytic enzymes collagenase ("collagenase-soluble" fraction) or pancreatic elastase ("elastase-insoluble" fraction) each contained approx. 87% of the total collagen initially present. 3. Both collagen fractions were chemically analysed for their amino acid and carbohydrate contents and were found to be similar to those of the intact interstitial collagens isolated from skin, bone and tendon. 4. The contents of the two aldimine cross-linking compounds, dehydrohydroxylysinonorleucine and dehydrodihydroxylysinonorleucine, were determined in the bovine pulmonary collagen fractions, and were found to decrease with increasing age of the animals, and were similar to the values found in intact collagens from bone and tendon.
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PMID:Isolation and chemical characterization of collagen in bovine pulmonary tissues. 16 65

1. An activator catalysing specifically conversion of latent forms of human leucocyte collagenase and gelatin-specific protease into the active forms, has been isolated from rheumatoid synovial fluid and purified 55-fold with a yield of 16%. 2. Molecular weight of the activator is about 35 000. 3. The activator is thermolabile, and is irreversibly inactivated at pH below 5.5 or in the presence of low concentrations of trypsin or papain; it is resistant to the action of lysozyme, hyaluronidase, diisopropylfluorophosphate, soybean trypsin inhibitor, p-chloromercuribenzoate, iodoacetamide and dithiothreitol. 4. The activator did not show any activity towards collagen, gelatin, casein, haemoglobin, histones, elastin or p-phenylazobenzyloxycarbonyl-peptide.
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PMID:Isolation, purification and properties of a factor from rheumatoid synovial fluid activating the latent forms of collagenolytic enzymes. 17 Jul 64

The low molecular weight bronchial protease inhibitor isolated from purulent bronchial secretions of man was shown to be a potent inhibitor of the elastase from human granulocytes. At a molar ratio of 1:1, the inhibitor prevented elastase digestion of insoluble elastin and soluble elastin, and blocked the hydrolysis of t-BOC-L-alanine-p-nitrophenyl ester. The collagenolytic activity of granulocyte collagenase was not inhibited by the bronchial inhibitor. Antisera were raised in rabbits for the isolation of specific IgG fractions in order to localize and quantitate the inhibitor. 125I-labelled inhibitor was used to study enzyme interactions further by gel filtration. These studies demonstrated that the bronchial inhibitor formed firm complexes with granulocyte elastase but did not form complexes with granulocyte collagenase.
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PMID:Inhibition of elastase from granulocytes by the low molecular weight bronchial protease inhibitor. 18 83


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