Gene/Protein
Disease
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Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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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 activity capable of excising in a single fragment the N-terminal extension of the precursor of collagen type III (p-N-collagen type III) was observed in calf tendon fibroblast culture medium. A new procedure was developed for detecting this peptidase (p-N-collagen type III peptidase). It is based on the use of 14C-labelled p-N-collagen type III obtained by carboxymethylation of the half-cystine residues with iodo-[14C]
acetamide
. The released labelled N-terminal extension is soluble in 27% (v/v) ethanol, whereas the uncleaved substrate and the collagen are precipitated under these conditions. The endopeptidase nature of p-N-collagen type III peptidase is supported by the similarity in molecular weight of the product of cleavage of p-N-collagen III by the enzyme to those obtained by cleavage with bacterial
collagenase
. An apparent Km of 0.3 X 10(-6)M was established. The pH optimum of p-N-collagen type III peptidase is similar to that of p-N-collagen type I peptidase, i.e. about 7.5. Both peptidases are inhibited by dithiothreitol and by Cu2+ and Zn2+, but not by other bivalent ions. p-N-collagen type III peptidase does not cleave p-N-collagen I or p-N-gelatin I. Partial purification of p-N-collagen type III peptidase from fibroblast culture medium was performed by sieve chromatography on Ultrogel AcA-34 to yield two peaks of activity, of mol.wts. 170000 and 100000. Part of the activity was retained on affinity chromatography on concanavalin A--Sepharose. Studied as a function of the age of the culture, p-N-collagen type III peptidase activity produced by tendon fibroblasts parallels that of p-N-collagen type I peptidase and collagen synthesis.
...
PMID:Procollagen type III N-terminal endopeptidase in fibroblast culture. 626 32
During water treatment, potentially hazardous chemical by-products may be formed. Alachlor (2-chloro-N-(2, 6-diethylphenyl)-N-(methoxymethyl)
acetamide
) is a widely used pre-emergence herbicide. The present study investigated the toxicity of alachlor and its disinfection by-products on freshly isolated rat hepatocytes. Hepatocytes were harvested by a
collagenase
perfusion technique and were exposed to different concentrations of alachlor and its by-products for up to 2 h. Cell viability, the leakage of aspartate transaminase (AST) and alanine transaminase (ALT) and glutathione (GSH) depletion were determined throughout the incubation period. The cell viability of the hepatocytes exposed to 100 microg ml(-1) alachlor was decreased by 20% compared with the control after 60 min of incubation. At the same concentration of alachlor the leakage of ALT and AST was increased by 56% and 45%, respectively. Cell viability of the hepatocytes was decreased upon exposure to 2-chloro-N-(3-chloro-2,6-diethylphenyl)-N-(methoxymethyl)
acetamide
(CCDMA) and 2-chloro-N-(3-chloro-2,6-diethylphenyl)
acetamide
(CCDA)--the by-products of alachlor and chlorine--after 60 min of exposure. At 100 microg ml(-1) CCDMA the AST leakage was increased significantly (73%) after 30 min of incubation. The reaction mixture of alachlor (100 microg ml(-1)) and chlorine dioxide (1 ppm) caused significant increases in cell loss and ALT and AST levels by 22%, 40% and 34%, respectively, as early as 15 min incubation. Alachlor (100 and 200 microg ml(-1)) caused significant decreases in GSH contents (62%) in isolated hepatocytes. The reaction mixture of alachlor and chlorine dioxide led to significant glutathione depletion (44%) after 60 min of incubation. The by-products of alachlor and chlorine--CCDMA and CCDA--depleted GSH almost completely (93%). This investigation suggested that the by-products formed from the reaction of alachlor and chlorine decreased GSH and increased the leakage of liver enzymes, especially AST.
...
PMID:In vitro hepatotoxicity of alachlor and its by-products. 1180 27
New inhibitors of tumor necrosis factor-alpha converting enzyme (TACE) were discovered using an N-hydroxy-2-(2-oxo-3-pyrrolidinyl)
acetamide
scaffold. The series was found to be potent in a porcine TACE (pTACE) assay with IC(50)s typically below 5 nM. For most compounds, selectivity for pTACE relative to
MMP-1
,-2, and -9 is at least 300-fold. Compound 2o was potent in inhibition of TNFalpha production in a human whole blood assay (WBA) with an IC(50) of 0.42 micro M.
...
PMID:Discovery of N-hydroxy-2-(2-oxo-3-pyrrolidinyl)acetamides as potent and selective inhibitors of tumor necrosis factor-alpha converting enzyme (TACE). 1278 Nov 90
The inhibitory activity (IC50) toward matrix metalloproteinases (
MMP-1
, MMP-2, MMP-3, MMP-9, and MMP-13) of N-hydroxy-2-[(phenylsulfonyl)amino]
acetamide
derivatives (HPSAAs) has been successfully modeled using 2D autocorrelation descriptors. The relevant molecular descriptors were selected by linear and nonlinear genetic algorithm (GA) feature selection using multiple linear regression (MLR) and Bayesian-regularized neural network (BRANN) approaches, respectively. The quality of the models was evaluated by means of cross-validation experiments and the best results correspond to nonlinear ones (Q2>0.7 for all models). Despite the high correlation between the studied compound IC50 values, the 2D autocorrelation space brings different descriptors for each MMP inhibition. On the basis of these results, these models contain useful molecular information about the ligand specificity for MMP S'1, S1, and S'2 pockets.
...
PMID:Linear and nonlinear QSAR study of N-hydroxy-2-[(phenylsulfonyl)amino]acetamide derivatives as matrix metalloproteinase inhibitors. 1650 15
A target-ligand QSAR approach using autocorrelation formalism was developed for modeling the inhibitory potency (pIC(50)) toward matrix metalloproteinases (
MMP-1
, MMP-2, MMP-3, MMP-9, and MMP-13) of N-hydroxy-2-[(phenylsulfonyl)amino]
acetamide
derivatives. Target and ligand structural information was encoded in the Topological Autocorrelation Interaction matrix calculated from 2D topological representation of inhibitors and protein sequences. The relevant Topological Autocorrelation Interaction descriptors were selected by genetic algorithm-based multilinear regression analysis and Bayesian-regularized genetic neural network approaches. A model ensemble strategy was employed for achieving robust and reliable linear and non-linear predictors having nine topological autocorrelation interaction descriptors with square correlation coefficients of ensemble test-set fitting (R(2)(test)) about 0.80 and 0.87, respectively. Electrostatic and hydrophobicity/hydrophilicity properties were the most relevant on the optimum models. In addition, the distribution of the inhibition complexes on a self-organized map depicted target dependence rather than an inhibitor similarity pattern.
...
PMID:Proteochemometric modeling of the inhibition complexes of matrix metalloproteinases with N-hydroxy-2-[(phenylsulfonyl)amino]acetamide derivatives using topological autocorrelation interaction matrix and model ensemble averaging. 1855 54