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)

Type III collagen was prepared from human liver by limited pepsin digestion, differential salt precipitation, and carboxymethylcellulose chromatography. Ten distinct peptides were obtained by cyanogen bromide digestion. The peptide alpha 1 (III)-CB5 was further purified by carboxymethylcellulose chromatography, and its amino acid sequence was determined. Automatic Edman degradation of intact alpha 1 (III)-CB5, tryptic and thermolytic peptides, and hydroxylamine-derived fragments was used to establish the total sequence. The mammalian collagenase site contained in the alpha 1 (III)-CB5 sequence was ascertained by digestion of native type III collagen with purified rheumatoid synovial collagenase. Collagenase cleavage occurred at a single Gly--Ile bond, one triplet before the corresponding specific cleavage site of type I collagen. The present work brings the known sequence of human liver type III collagen to include alpha 1 (III)-CB3-7-6-1-8-10-2-4-5. These correspond to the homologous region of alpha 1 (I)-CB0-1-2-4-5-8-3-7 residues 11--804.
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PMID:Covalent structure of collagen: amino acid sequence of alpha 1 (III)-CB5 from type III collagen of human liver. 624 25

A study of the influence of chemical modifications on the activity of Achromobacter iophagus collagenase (EC 3.4.24.8) has led to the following conclusions: a modification of 4 out of 80 COOH groups with carbodiimide led to 90% loss of enzymic activity. A 70% inactivation was found after modification of two tyrosines out of 30 with tetranitromethane. The modification of four to six tryptophans out of 16 with 2-hydroxy-5-nitrobenzyl bromide decreased enzyme activity to 36%. This inactivation is accelerated in the presence of collagen. An increase of reagent/enzyme molar ratio led to a modification of 16 tryptophan residues and denaturation of Acahromobacter collagenase. A modification of two arginines out of 18 with 1,2-cyclohexanedione and eight NH2 groups out of 24 with 2,3-dimethyl maleic anhydride does not change the collagenolytic activity. All NH2 groups become available for 2,3-dimethyl maleic anhydride after dissociation of the dimer. A possible analogy of hydrolytic site of collagenase with that of two other known bacterial metalloproteinases (thermolysin and Bacillus subtilis neutral proteinase (EC 3.4.24.4)) is discussed.
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PMID:Chemical modifications of Achromobacter collagenase and their influence on the enzymic activity. 625 92

The amino acid sequence of a collagenolytic protease from the hepatopancreas of the fiddler crab, Uca pugilator, was determined from the structures of overlapping tryptic, chymotryptic, thermolytic, staphylococcal protease, and cyanogen bromide peptides together with automated sequencer analysis of the intact protein. Crab collagenase is a serine protease composed of 226 residues which is capable of degrading the native triple helix of collagen under physiological conditions. When aligned for optimal homology, crab collagenase displays 35% identity with bovine trypsin, 38% with bovine chymotrypsin B, and 32% with porcine elastase. The six half-cystinyl residues in crab collagenase correspond to those forming three of the five disulfide bonds in chymotrypsin. The residues forming the charge relay system of the active site of chymotrypsin (His-57, Asp-102, and Ser-195) are found in corresponding regions in crab collagenase, and the sequences around these residues are well conserved. The primary structure of crab collagenase is the first reported for a serine protease from crustacean hepatopancreas and the first reported for a serine protease possessing the unusual property of being able to degrade native helical collagen.
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PMID:Amino acid sequence of a collagenolytic protease from the hepatopancreas of the fiddler crab, Uca pugilator. 625 53

A unique collagen, designated EC, has been isolated from the culture medium of adult bovine aortic endothelial cells. After diethylaminoethylcellulose chromatography of [3H]proline-labeled culture medium, three non-disulfide-bonded bacterial collagenase-sensitive components with apparent Mr of 177000 (EC 1), 125000 (EC 2), and 100000 (EC 3) were demonstrated. Molecular sieve chromatography, cyanogen bromide cleavage, and two-dimensional peptide mapping of radioiodinated EC fragments produced by protease digestion suggest that the lower molecular weight components originate from EC 1. Both EC 1 and EC 2 were digested by pepsin within 10 min to products of less than 60000 molecular weight, under conditions which supported only limited proteolysis of other native collagens. A pepsin-resistant fragment of Mr 50000, derived from a digest of EC 2, contained equal amounts of hydroxyproline and proline, suggesting that at least a portion of the endothelial collagen contains a stable, collagen-like triple helix. Comparative mapping using mast cell protease and cyanogen bromide cleavage, followed by polyacrylamide gel electrophoresis, indicates that the primary structure of this collagen differs from that of other known collagen types.
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PMID:A unique, pepsin-sensitive collagen synthesized by aortic endothelial cells in culture. 625 89

The soluble material produced from a 96-hour digest of sonicated human glomerular basement membranes with purified collagenase was shown to contain at least 12 components by sodium dodecyl sulphate-polyacrylamide gel electrophoresis with molecular weights ranging from 20 x 10(3) to greater than 200 x 10(3) daltons. Five of these components produced antigenic peaks after two-dimensional immunoelectrophoresis into agar plates containing rabbit antiserum to the solubilised glomerular basement membrane. Two groups of antigenic components were demonstrated in these gels by two-dimensional immunoelectrophoresis autoradiographic techniques utilising 125I-labelled collagenase-digested human glomerular basement membranes reacted with antibodies eluted at acid pH from the kidney of the Goodpasture's patient. This acid eluate was shown to contain contaminants of alpha 1-antitrypsin and albumin co-eluting with the antibodies bound to the glomerular basement membrane. After removal of these contaminants, the antibodies were linked to cyanogen bromide-activated Sepharose and used to affinity purify four antigenic fractions from the collagenase-digested glomerular basement membrane. These fractions were eluted by 0.2 M glycine pH 2.8 and with 0.5 M ammonium thiocyanate and had molecular weights of 22-25, 43-45, 65-70 and 205 x 10(3) daltons. The smaller molecular weight components were shown to be common to both included and excluded fractions obtained by Ultragel AcA 44 chromatography of the digested material in 10 mM phosphate pH 8. This suggests that the larger molecular weight component would be an aggregate of a smaller component. Preliminary carbohydrate and amino acid analyses indicated that the different elution procedures elicited antigens with different chemical characteristics.
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PMID:Isolation of human glomerular basement membrane antigens by affinity chromatography utilising Goodpasture's kidney antibody eluates. 627 70

Acetic acid-pepsin extracts of normal human corneal stromas were shown by carboxymethyl cellulose-column chromatography, sodium dodecyl sulfate-slab gel electrophoresis, highly purified collagenase, trypsin sensitivity, and cyanogen bromide peptide mapping to contain types I, III, and IV collagen, with type I by far the predominant species. This degree of collagen heterogeneity in normal human corneal stroma has not been reported previously and may be important in the understanding of wound healing and disease states.
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PMID:Human corneal stroma contains three distinct collagens. 627 19

Corneal endothelial cells in culture synthesize basement membrane collagen and secrete it into the medium. This collagen sediments faster than interstitial collagen by velocity sedimentation and is disulfide-bonded. After reduction, two biochemically distinct chains can be determined by cyanogen bromide peptide mapping. These chains migrate close to each other and immediately below beta 12(I) components on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Treatment with pepsin gives rise to a major band which still retains interchain disulfide bonds and which will not convert to components with the mobility of interstitial alpha chain by reduction. However, an alpha chain and three minor collagenase-sensitive and pepsin-resistant peptides are generated if the molecule is reduced and alkylated under nondenaturing conditions prior to pepsin treatment. When collagen which accumulates in the media over a long period of time is compared to the newly synthesized molecules, there is an apparent differential resistance to limited pepsin treatment. However, the products which are generated in both cases share electrophoretic identity.
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PMID:Basement membrane collagen synthesis by rabbit corneal endothelial cells in culture. Evidence for an alpha chain derived from a larger biosynthetic precursor. 628 31

Peripheral blood mononuclear cells from patients with rheumatoid arthritis (n = 27), systemic lupus erythematosus (n = 24), juvenile rheumatoid arthritis (n = 30), osteoarthritis (n = 20), apparently healthy adults (n = 12), and nonarthritic children (n = 8) were exposed to several putative connective tissue antigens to determine if the monokine, mononuclear cell factor, was released. Release of this factor was detected by bioassay in which enhancement of collagenase production from human synovial cells or dermal fibroblasts was measured. The antigens, all of homologous tissue origin, included cyanogen bromide-derived peptides of type I, II, and III collagens, type I and II helical collagens, and cartilage proteoglycan. Of the subjects examined, 44% of the rheumatoid group, 42% of the systemic lupus group, 33% of the juvenile rheumatoid group but only 10% of the osteoarthritic group and 5% of the control group released monokine after exposure of peripheral blood mononuclear cells to at least one of these connective tissue antigens. Patients with rheumatoid arthritis most frequently responded to type II peptides (but not to type II helical collagen) although the frequencies of responses to type I peptides, type I helical collagen and proteoglycan were also elevated over levels observed in the control population. Positive responses in these patients typically occurred to only one antigen, were transient, often occurred close to the onset of arthritis, and appeared to be unrelated to disease activity. The profiles of responses in patients with juvenile rheumatoid arthritis and systemic lupus shared many features in common and were distinct from those of adult rheumatoid arthritis. Patients with systemic lupus or juvenile rheumatoid arthritis responded to all of the antigens tested. Positive responses often occurred simultaneously to several antigens. Responses to type II helical collagen were most common while sensitization to type II peptides was infrequently detected. Positive responses were transient, unrelated to overall disease activity, type of juvenile arthritis, or duration of disease in lupus patients. Stimulation of mononuclear cell factor release by connective tissue molecules and their degradation products may make an important contribution to the chronic inflammation commonly seen in these diseases.
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PMID:Connective tissue antigens stimulate collagenase production in arthritic diseases. 632 85

A low molecular weight fraction (Mr = 500-1500) was isolated by membrane and gel filtration from rat embryonic brain extract. This fraction was shown to stimulate collagen production in muscle cultures. Procollagen, intermediate collagenous proteins, and collagens of types I, III, and V were identified by analysis on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and DEAE- and Cm-cellulose chromatography and by selective degradation by pepsin, bacterial collagenase, and cyanogen bromide. Immunofluorescent staining with antisera to collagen types I, III, IV, and V of muscle cultures treated with the collagen-inducing factor revealed a large increase in staining compared to control cultures and a distinct pattern of staining on the surface of the treated myotubes.
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PMID:Characterization and localization of collagens synthesized by cultured muscle cells stimulated with collagen-inducing factor from embryonic brain extracts. 635 23

Calf aortic smooth muscle cell cultures produce both type III and type I collagen. Polyadenylated mRNA species purified from these cells direct the synthesis of prepro-alpha 1(III), prepro-alpha 1(I), and prepro-alpha 2(I) in a rabbit reticulocyte cell-free system. These polypeptides were identified by specific immunoprecipitation, cyanogen bromide peptide mapping, and bacterial collagenase digestion. Lower molecular weight collagenase susceptible polypeptides were also produced in translation reactions incubated under conditions optimized for incorporation of radiolabeled amino acids. Their presence did not appear to result from ribonuclease or protease involvement or from premature termination. Increasing the Mg2+ concentration in the translation system significantly reduced the production of these lower molecular weight species. Pulse-chase experiments indicate that the time required for completion of full length preprocollagen at the high Mg2+ concentration is greatly decreased compared to the low concentration. Additional experiments suggest that the incomplete collagen polypeptides result from pausing of ribosome movement during elongation. The relative synthesis of type III and type I chains was examined as a function of mRNA concentration in the cell-free system. At levels of RNA above saturation, the relative production of type III decreased with respect to type I. These data suggest that the ability of the alpha 1(III) mRNA to initiate translation is less efficient than the mRNAs of alpha 1(I) and alpha 2(I).
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PMID:Cell-free translation of calf type III collagen. Effect of magnesium on ribosome movement during elongation. 661 53


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