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)

To assess the differences in proteolytic activity of acute and chronic wound environments, wound fluids were collected from acute surgical wounds (22 samples) and chronic wounds (25 samples) of various etiologies, including mixed vessel disease ulcers, decubiti and diabetic foot ulcers. Matrix metalloproteinase (MMP) activity measured using the Azocoll assay was significantly elevated by 30 fold in chronic wounds (median 22.8 microg MMP Eq/ml) compared to acute wounds (median 0.76 microg MMP Eq/ml) (p < 0.001). The addition of the matrix metalloproteinase inhibitor Illomostat decreased the matrix metalloproteinase activity by approximately 90% in all samples, confirming that the majority of the activity measured was due to matrix metalloproteinases. Gelatin zymograms indicated predominantly elevated matrix metalloproteinase-9 with smaller elevations of matrix metalloproteinase-2. In addition tissue inhibitor of metalloproteinase-1 levels were analyzed in a small subset of acute and chronic wounds. When tissue inhibitor of metalloproteinase-1 levels were compared to protease levels there was an inverse correlation (p = 0.02, r = - 0.78). In vitro degradation of epidermal growth factor was measured by addition of 125I labelled epidermal growth factor to acute and chronic wound fluid samples. There was significantly higher degradation of epidermal growth factor in chronic wound fluid samples (mean 28.1%) compared to acute samples (mean 0.6%). This also correlated to the epidermal growth factor activity of these wound fluid samples (p < 0. 001, r = 0.64). Additionally, the levels of proteases were assayed in wound fluid collected from 15 venous leg ulcers during a nonhealing and healing phase using a unique model of chronic wound healing in humans. Patients with nonhealing venous leg ulcers were admitted to the hospital for bed rest and wound fluid samples were collected on admission (nonhealing phase) and after 2 weeks (healing phase) when the ulcers had begun to heal as evidenced by a reduction in size (median 12%). These data showed that the elevated levels of matrix metalloproteinase activity decreased significantly as healing occurs in chronic leg ulcers (p < 0.01). This parallels the processes observed in normally healing acute wounds. This data also supports the case for the addition of protease inhibitors in chronic wounds in conjunction with any treatments using growth factors.
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PMID:Analysis of the acute and chronic wound environments: the role of proteases and their inhibitors. 1063 3

Two different endopeptidases which digest the chromogenic substrate Azocoll were found in soybean leaves. Azocollase A has a molecular weight of 17,500 and a pI of 6.0. Azocollase B has a molecular weight of 52,000 and a pI of 9.0. Both digest Azocoll optimally at pH 9.0. Azocollase A is inhibited by 3 millimolar ethylenediamine tetraacetate (EDTA) and azocollase B by 100 micromolar parachloromercuribenzoate. Studies on whole plants grown in the greenhouse and in the field show that total azocollase activity gradually increased during leaf maturation when leaf protein and chlorophyll increased, and then declined again during leaf senescence. Young leaves which are still expanding contain mostly azocollase B and little azocollase A. Leaf maturation was associated with a dramatic increase in azocollase A (40- to 50-fold), while azocollase B activity increased more slowly. This increase in azocollase A occurred in the 2- to 3-week period following leaf expansion. Azocollase A, separated from other proteinases by gel filtration on Sephadex G-100, digested denatured leaf protein and casein, resulting in the release of free alpha-amino groups. Break-down of leaf proteins by autodigestion of extracts at pH 9.0 resulted in the release of free alpha-amino groups and endopeptidic cleavage of polypeptides. However, polypeptide cleavage was not inhibited by parachloromercuribenzoate or EDTA indicating that the azocollases do not play a major role in the hydrolysis of leaf proteins in crude extracts.
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PMID:Azocoll-digesting Proteinases in Soybean Leaves: Characteristics and Changes during Leaf Maturation and Senescence. 1666 Oct 69


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