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)

Attempts to design an agent which would release cytotoxic nitrogen mustards within collagenase-producing tumors led to the synthesis of Cbz-L-Pro-L-Leu-Gly-L-Pro-Gly-NHC6H4N(CH2CH2Cl)2 (10). 10 was cleaved in vitro by bacterial and tumor-associated collagenase as expected at the peptide bond joining L-leucine and glycine to give Gly-L-Pro-Gly-NHC6H4N(CH2CH2Cl)2 which was over six times more toxic, on a molar basis, than 10. In vivo tests of 10 against well-advanced Sarcoma-180 gave disappointing results. The lack of specific antitumor activity may be accounted for by the presence of competing cleavage reactions by collagenases in certain normal tissues.
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PMID:Collagenase-sensitive peptidyl-nitrogen mustards as potential antitumor agents. 21 58

Equine kidney cells disaggregated by treatment with 0.01% collagenase were used in the preparation of primary monolayer cell cultures. The primary cells could be stored for long periods in liquid nitrogen and subsequently subcultivated. These techniques provided a long-term supply of equine kidney cells, free of apparent contamination, from the kidneys of a single fetus.
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PMID:Collagenase in equine cell culture preparation. 22 24

1. The age-related decrease in hydroxyproline : creatinine ratio in young guinea pigs was significantly smaller in vitamin C-deficient animals than in pair-fed controls. The same was true for proline : creatinine and total amino nitrogen : creatinine ratios, but hydroxyproline : total amino nitrogen and proline : total amino nitrogen ratios were not significantly affected by deficiency. 2. Although the proline : hydroxyproline ratio was unaffected in unfractionated urine, acute or chronic deficiency produced a small but significant increase in this ratio in collagenase digests of the acetone-insoluble fraction. 3. In scorbutic animals, therefore, collagen probably turns over more rapidly than in animals matched for inanition. Some at least, of this increase could represent the rapid turnover of underhydroxylated nascent collagen. Because it contains the degradation products from collagen from many tissues, differing widely in sensitivity to vitamin C status, the urine is unlikely, however, to provide a specific and sensitive functional index of vitamin C status.
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PMID:Vitamin C deficiency in guinea pigs: changes in urinary excretion of proline, hydroxyproline and total amino nitrogen. 46 70

To clarify the relationship between air pollution and mast cell response, the effects of sulfuric acid aerosols on histamine release from lung mast cells of guinea pigs were investigated. Guinea pigs were exposed to 0.3, 1.0 and 3.2 mg/m3 sulfuric acid (H2SO4) aerosols or 4 ppm nitrogen dioxide (NO2) for 2 and 4 weeks. After the exposure, lung mast cell suspensions were isolated by collagenase treatment and antigen- or A23187-induced histamine release was measured. Antigen-induced histamine release from mast cells was significantly enhanced by the exposure to 1.0 and 3.2 mg/m3 H2SO4 for 2 weeks, but exposure to H2SO4 for 4 weeks did not show the enhancement of antigen-induced histamine release. A23187-induced histamine release was significantly enhanced by the exposure to 1.0 mg/m3 H2SO4 or 4 ppm NO2 for 2 weeks, but suppression of histamine release from lung mast cells stimulated with A23187 was observed by the exposure to 3.2 mg/m3 H2SO4 for 4 weeks. The exposure to 0.3 mg/m3 H2SO4 showed no changes in antigen- and A23187-induced histamine release. The combination of 1.0 mg/m3 H2SO4 with 4 ppm NO2 for 2 weeks resulted in no changes in antigen- and A23187-induced histamine release. These results suggested that functional properties of lung mast cells may be altered by a low concentration of H2SO4 aerosol exposure.
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PMID:Enhanced histamine release from lung mast cells of guinea pigs exposed to sulfuric acid aerosols. 137 9

A gamete lytic enzyme (GLE) of Chlamydomonas reinhardtii is a zinc metalloprotease and mediates digestion of the cell walls of the two mating-type gametes during mating as a necessary prelude to cell fusion. The nucleotide sequence analysis of a cDNA revealed that GLE is synthesized in a preproenzyme form, a 638-amino acid polypeptide (Mr, 69,824) with a 28-amino acid signal peptide, a 155-amino acid propolypeptide, and a 455-amino acid mature polypeptide (Mr, 49,633). A potential site for autocatalytic activation was contained within the propolypeptide and a zinc binding site found within the mature polypeptide; both sites were highly homologous to those in mammalian collagenase. A putative calcium binding site was present in the near C-terminal region of the mature GLE. Both propolypeptide and mature polypeptide had potential sites for asparagine-linked glycosylation, and the Arg-(Pro)3 and Arg-(Pro)2 motifs, which are known to exist in hydroxyproline-rich glycoproteins of the Chlamydomonas cell wall. Northern blot analysis revealed that steady-state levels of the 2.4-kilobase GLE mRNA increased during growth and mitotic cell division in the vegetative cell cycle and also increased markedly during gametogenesis under nitrogen-starved conditions.
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PMID:Primary structure and expression of a gamete lytic enzyme in Chlamydomonas reinhardtii: similarity of functional domains to matrix metalloproteases. 158 6

A hot aqueous extract of Coptidis Rhizoma had an inhibitory effect on the bacterial collagenase from Clostridium histolyticum. Active principles were isolated by silica gel column chromatography from the CHCl3 extract. Consequently, two inhibitors obtained were identified with the chloride of berberine and coptisine. The concentrations of the berberine and coptisine in the assay mixture to give 50% inhibition (IC50) were 0.73 mM and 0.16 mM, respectively. The type of inhibition by coptisine chloride was shown to be a mixture type from Lineweaver-Burk plots. Tetrahydroberberine, a reduction product of berberine chloride, had no inhibitory effect. This result suggests that the quaternary nitrogen of the alkaloids plays an important role in inhibitory activity.
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PMID:[Studies on collagenase inhibitors. IV. Inhibitors of bacterial collagenase in Coptidis rhizoma]. 166 69

Sixteen clinical isolates comprising six each of type A and type B of Hendersonula toruloidea, three of Scytalidium hyalinum and one of S. japonicum were investigated for their physiological characteristics. All the isolates utilized 13 carbon sources and three nitrogen sources tested and grew in a medium containing 3.7 M NaCl. A concentration of 4.5 M NaCl inhibited the growth of all the isolates. The isolates produced amylase, lipase and protease but failed to produce collagenase.
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PMID:Physiological characteristics of clinical isolates of Hendersonula toruloidea and Scytalidium species. 182 May 14

In vivo and in vitro experiments were conducted in an effort to elucidate the mechanism of suppression by halofuginone of skin strength in broilers. In the in vivo study, halofuginone was included at concentrations of 0, 1.5, 3, and 6 mg/kg of diet, corresponding to 0, 50, 100, and 200%, respectively, of the amount recommended for use as a coccidiostat. Each dietary treatment was given to 260 female broiler day-old chickens. Skin tearing was evaluated at the processing plant. Skin collagen and Kjeldahl-nitrogen were determined chemically. At the age of 7 wk, BW and feed efficiency were affected only in birds consuming the diet containing the highest concentration of the drug. Skin tearing increased but skin collagen concentration decreased in a dose-dependent manner. Fibroblasts were obtained by collagenase digestion from chicken skin and cultured. The cultured cells were incubated with various concentrations of halofuginone, monensin, and nicarbazin, and [3H]proline incorporation was evaluated in collagenase-digestible (representing mostly collagen) and nondigestible proteins exported by the cells into the medium. Halofuginone, at a concentration as low as 10(-11) M, inhibited incorporation of [3H]proline into collagenase-digestible proteins, but did not affect incorporation of [3H]proline into collagenase-nondigestible proteins. Even at concentrations as high as 10(-9) M, neither monensin nor nicarbazin affected collagenase-digestible proteins. The in vitro results suggest that halofuginone specifically inhibits collagen synthesis by skin fibroblasts. Results of both in vivo and in vitro trials suggest that the increase of skin tearing during processing, induced by halofuginone, is caused by direct suppression of skin collagen synthesis.
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PMID:Increased skin tearing in broilers and reduced collagen synthesis in skin in vivo and in vitro in response to the coccidiostat halofuginone. 188 67

To get a better understanding of the possible role of proteases in the pathogenesis of fungal keratitis, the extracellular proteases of a clinical isolate of Aspergillus flavus, from a severe case of keratitis, were identified and partially characterized. This strain, designated CU226/88, was grown with a variety of substrates as nitrogen sources, under conditions that would be expected to derepress the production of extracellular proteases. When grown on minimal medium with milk protein as a nitrogen source, the fungus appeared to produce primarily a metalloprotease, which has a zinc cofactor. When grown with insoluble collagen or elastin as a nitrogen source, a serine protease and cysteine protease, as well as the metalloprotease, are produced. Strain CU226/88 can grow with collagen, but not elastin, as the sole source of carbon as well as nitrogen. It is possible that the collagenase activity is a mediator of the severe corneal destruction caused by this isolate.
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PMID:Extracellular proteases of Aspergillus flavus. Fungal keratitis, proteases, and pathogenesis. 217 95

Cryopreservation of human parathyroid tissue plays an important role in managing difficult parathyroid disease. It also can permit investigators to conduct experiments without dependence on the operating room schedule. Availability of cryopreservation has been limited by the perceived need for expensive, complex equipment. We adapted a simple method of freezing cell suspensions to freezing human parathyroid tissue. Vials containing human parathyroid in culture media, dimethylsulfoxide, and patient serum were placed in a plastic rack in a metal pan containing prechilled (4 degrees C) ethanol and placed in a -70 degrees C freezer. We compared viability (trypan blue dye exclusion by collagenase dispersed cells) of tissue frozen in this manner to that of tissue frozen in a programmable liquid nitrogen freezer at 1 degrees C per minute, a cooling rate recommended for human parathyroid tissue. The viability of 30 patients' samples cooled in liquid nitrogen (average length of storage 5 months) was 74% +/- 15% and that of 64 patients' samples cooled in ethanol (average length of storage 26 months) was 71% +/- 15%. Viability of 19 samples of fresh tissue was 79% +/- 10%. Neither method had a statistically significant correlation between length of storage and viability. Successful cryopreservation with simplified technology may expand the availability of parathyroid tissue to meet both clinical and investigative requirements.
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PMID:Characterization of a simplified method of cryopreserving human parathyroid tissue. 224 27


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