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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)
Endothelial cells isolated from bovine aorta synthesize and secrete type III procollagen in culture. The procollagen, which represents the major collagenous protein in culture medium, was specifically precipitated by antibodies to bovine type III procollagen and was purified by diethyl-aminoethylcellulose chromatography. Unequivocal identification of the
pepsin
-treated collagen was made by direct comparison with type III collagen isolated by
pepsin
digestion of bovine skin, utilizing peptide cleavage patterns generated by vertebrate collagenase, CNBr, and mast cell protease. The type III collagen was hydroxylated to a high degree, having a hydroxyproline/proline ratio of 1.5:1.0. Pulse-chase studies indicated that the procollagen was not processed to procollagen intermediates or to collagen. Pepsin treatment of cell layers, followed by salt fractionation at acidic and neutral pH, produced several components which were sensitive to bacterial
collagenase
and which comigrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with alpha A, alpha B, and type IV collagen chains purified from human placenta by similar techniques. Bovine aortic endothelial cells also secreted fibronectin and a bacterial
collagenase
-insensitive glycoprotein which, after reduction, had a molecular weight of 135,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (using procollagen molecular weight standards) and which was not precipitable by antibodies to cold-insoluble globulin or to alpha 2-macroglobulin. Collagen biosynthesis by these cells provides an interesting model system for studying the polarity of protein secretion and the attachment of cells to an extracellular matrix. The presence of type III collagen in the subendothelium and the specific interaction of this protein with fibronectin and platelets suggest the involvement of this collagen in thrombus formation following endothelial cell injury.
...
PMID:Collagen synthesis by bovine aortic endothelial cells in culture. 39 Dec 67
Fibroblasts isolated by enzymic digestion of chick embryo tendons were incubated for several hours in suspension under conditions in which they were in steady state in terms of the synthesis and secretion of procollagen. Under these conditions, the cells synthesized and secreted about 630 microgram of procollagen/10(9) cells/h. The cells were labeled with [14C]proline for 15 to 120 min and then the kinetics of secretion were followed by chasing the label and assaying the 14C-peptides digestible by
collagenase
in the cells and in the medium. The results demonstrated that secretion of
collagenase
-digestible peptides did not follow the kinetics of a single first order process but suggested at least two pseudo-first order process with half-times of 14 and 115 min. The [14C]procollagen secreted during 0 to 30 min and 90 to 120 min of chase was the same in terms of the ratio of pro-alpha1 to pro-alpha2 chains, the size of the pro-alpha chains, the extent of interchain disulfide bonding, the extent of prolyl hydroxylation, and the degree of helicity as tested by resistance to
pepsin
digestion. Addition of ascorbic acid to the incubation medium increased slightly the extent of prolyl hydroxylation but did not alter the kinetics of secretion. The results suggested that the kinetics of secretion are influenced by a two-compartment system in which at least one metabolic pool contributing to the secretory process is present as a "side pocket."
...
PMID:Kinetics for the secretion of procollagen by freshly isolated tendon cells. 56 77
Synovial tissues from 5 patients with rheumatoid arthritis (RA) were examined with immunofluorescence microscopy for the presence of lymphocytes with either bone marrow-derived (B) or thymus-derived (T) surface markers. Five synovial tissues with severe to mild lymphocytic infiltrations by bright field microscopy were examined in parallel with immunofluorescence. B cells were identified with a
pepsin
-digested fluoresceinated anti-F (ab')2 antiserum and T cells were detected with a specific rabbit anti-T lymphocyte antiserum. By these techniques 75-90% of the lymphocytes in these frozen sections were identified as T cells. Cell suspensions were also prepared by
collagenase
digestion of two of the five synovial tissues. The lymphocytes in these cell suspensions were predominantly T lymphocytes (78-85%) as shown by their ability to form spontaneous rosettes with sheep erythrocytes (E rosettes).
...
PMID:Predominance of T cells in the lymphocytic infiltrates of synovial tissues in rheumatoid arthritis. 77 95
This study describes the use of the radioimmunoassay for the characterization of antibodies to basement membrane (type IV) collagen from bovine anterior lens capsule. The immunogen was extracted from calf anterior lens capsules by limited
pepsin
digestion and injected into rabbits. The antisera were characterized using gel diffusion, haemagglutination and the radioimmunoassay in which 125I-labelled types I, II, III, and IV bovine collagen were employed. In the direct radioimmunoassay there was no reaction with either native or denatured types I, II or III bovine collagen, whereas there were high titres towards both native and denatured type IV bovine collagen. Radioimmune inhibition studies using unlabelled types I, II, III and IV bovine collagen,
collagenase
digested and repepsinized type IV collagen showed that there was marked inhibition by either native, denatured or repepsinized type IV collagen, and slight inhibition by native type I collagen; native type II and type III, denatured types I, II and III, and
collagenase
digested type IV collagen had no inhibitory effects.
...
PMID:The use of the radioimmunoassay in the characterization of antibodies to basement membrane collagen. 97 32
1. Anti-aortic antibodies were frequently detected from the sera of patients with aortitis syndrome. 2. Aortic antigens were demonstrated to exist mainly in the media. The antigenicity was inactivated by
collagenase
, trypsin and
pepsin
, but not by DNase-I. Analyses of aortic antigens were also made by ultracentrifugation and column chromatography. 3. Experimental arteritis could be produced in animals by isologous active immunization and heterologous passive immunization. 4. From these results, participation of antigen-antibody reaction in the development of the disease has been speculated. Possible role of streptococcal infection as one of the trigger mechanisms in antibody production has been suggested in combination with evidence indicating hypersensitivity of the patients to infections.
...
PMID:Immunological aspects of aortitis syndrome. 112 Oct 58
The insoluble component of stratum corneum of rat epidermis yields two major bands after extraction with 8 M urea-mercaptoethanol-dithiothreitol. The ratio of these two bands is about 1:1 in terms of protein stain intensity and S-[14C]carboxymethyl label. Both polypeptides were purified to homogeneity by DE-52-cellulose, sodium dodecyl sulfate hydroxylapatite C column chromatography, and preparative DodSO4-polyacrylamide gel electrophoresis. The heavier polypeptide contains 30% alpha helix and the lighter contains 27% alpha helix as determined by circular dichroism studies. Both are sensitive to Pronase and resistant to trypsin,
collagenase
, and elastase. The lighter chain is stable to
pepsin
but the heavier can be partially degraded to a smaller polypeptide with a molecular weight similar to that of light chain. Amino acid analysis shows that the light chain contains 12 more tyrosine residues than does the heavy chain, suggesting that the light chain is not generated from the heavy chain. However, the two chains may have a common peptide region. Antiserum prepared against the heavier polypeptide can be completely absorbed by purified lighter polypeptide and vice versa indicating that both chains have some common antigenic determinants. Antibody against either chain can cross-react with the stratum corneum and keratohyalin granules in the epidermis of newborn rat as indicated by fluorescent microscopic observation. Similarly, this antibody also cross-reacts with the cell surface or the contents of spinous and granular cells, and very weakly with basal cells, indicating that the two proteins may be present in the lower strata as well as the stratum corneum.
...
PMID:Two polypeptide chain constituents of the major protein of the cornified layer of newborn rat epidermis. 116 97
The ability of collagen and collagen-derived peptides to act as chemotactic stimuli was investigated by in vitro chemotaxis assays. Native human and chick skin collagen (type I) and alpha-chains obtained from purified chick skin collagen were each chemotactic for human peripheral blood monocytes. In addition, smaller peptides obtained either by digesting native collagen with bacterial
collagenase
or by degrading purified alpha-chains with cyanogen bromide or
pepsin
were also chemotactic for monocytes. In contrast, native collagen, alpha-chains, and smaller collagen-derived peptides were not chemotactic for human neutrophils. Since collagen is degraded at sites of tissue damage and inflammation, our findings suggest the possibility that such collagen-derived degradation products might directly serve as chemotactic stimuli for human peripheral blood monocytes in vivo.
...
PMID:Collagen-and collagen peptide-induced chemotaxis of human blood monocytes. 127 Oct 12
Fibroblasts cultured in a collagen gel contract and organize the gel into a three-dimensional matrix of collagen fibers. Within this matrix, the fibroblast cell cycle is blocked at the G1 phase but also at the G2 phase. The fibroblasts produce the main extracellular matrix components (collagen, noncollagen proteins, glycosaminoglycans), although in small amounts. Studies using this in vitro model with radiolabeled precursor substances (14C proline, 3H glucosamine) demonstrated production of supermolecular complexes which resisted to proteolysis by
pepsin
and
collagenase
and could not be isolated by saline precipitation. Polyclonal antibodies identified type I collagen, type VI collagen and fibronectin in this coherent supermolecular structure. The presence of glycosaminoglycans was also demonstrated by alcian blue precipitation.
...
PMID:[Synthesis and supramolecular organization of components of the extracellular matrix by fibroblasts cultured in a collagen lattice]. 129 57
A new molecule, type XIV collagen, with domains homologous to type IX and XII collagens has been recently discovered in
pepsin
extracts of fetal bovine tissues (Dublet, B., and van der Rest, M. (1991) J. Biol. Chem. 266, 6853-6858). In the present study, we describe the purification and the characterization of the intact native form of this newly discovered collagen. By using only two chromatographic steps we were able to obtain pure type XIV collagen. Furthermore, minor modifications of the protocol allowed us to perform the simultaneous large scale purification of type XII and type XIV collagens from the same tissue. Intact type XIV collagen migrates on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) as two bands of 220 and 290 kDa (reducing conditions). After
collagenase
treatment, a single band of 190 kDa is observed, which represents the large non-collagenous domain of the molecule (NC3). Rotary shadowing electron micrographs of intact type XIV collagen show a cross-shaped structure formed by a thin tail attached through a central globule to three identical "fingers." These properties are similar to those previously described for intact chicken type XII collagen (Dublet, B., Oh, S., Sugrue, S. P., Gordon, M. K., Gerecke, D. R., Olsen, B. R., and van der Rest, M. (1989) J. Biol. Chem. 264, 13150-13156), but the two molecules are different gene products and have charge and glycosylation differences. Finally, we show that the three chains of purified type XIV collagen have an apparent molecular mass of approximately 220 kDa and are not cross-linked to each other by bonds other than disulfide bridges. The same observation was made for type XII collagen. In both cases, the 290-kDa migrating band in SDS-PAGE is due to incomplete denaturation in electrophoresis sample buffer in the absence of urea.
...
PMID:Purification and characterization of native type XIV collagen. 132 5
Two monoclonal antibodies, designated 1F8 (IgG1) and 5B10 (IgG1), have been produced in mice against native human type III collagen. These antibodies were highly type and species specific, recognizing the triple helical domain of type III as tested by ELISA. Immunofluorescence studies using each of these antibodies resulted in a fibrous staining pattern in human skin dermis. Immunogold electron microscopy resulted in a periodic distribution of gold particulates along banded collagen fibrils. Assuming that the total contour length of
pepsin
digested type III collagen is 300 nm, measurements of antibody-antigen complexes visualized by rotary shadowing revealed that each antibody bound at the same two sites: one approximately at the middle of the helix (153 nm from the N-terminus), the other at a site one-quarter the triple helical length from the N-terminus (75 nm). That the one-quarter binding site was closest to the N-terminus was determined by antibody incubation following tadpole
collagenase
treatment, which results in a larger, N-terminus containing fragment (binding antibody) and a smaller C-terminus containing fragment (not binding antibody). Located at each antibody binding epitope is a sequence of 10 amino acids: Gly-Ala-Hyp-Gly-Leu-Arg-Gly-Gly-Ala-Gly. Renatured cyanogen bromide-cleaved(CB)-peptides, CB4 and CB8, containing these repeated sequences reacted with each antibody, whereas other renatured type III CB-peptides were unreactive as determined by Western blotting analysis and ELISA. This was further confirmed by inhibition tests using a 10 residue synthetic peptide of identical sequence, which yielded 20-30% inhibition of antibody binding to native type III collagen at 4 degrees C. However, no inhibition was noted at higher temperature. These results indicate that both monoclonal antibodies recognize a specific helical conformation of 10 or slightly fewer residues in the three identical polypeptide chains comprising type III collagen.
...
PMID:Repeated helical epitopes of defined amino acid sequence in human type III collagen identified by monoclonal antibodies. 137 14
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