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)

We have investigated the production of collagenous proteins by primary cultures of rat lung epithelial cells (type II pneumocytes). Three major bacterial collagenase-sensitive chains were synthesized and secreted into the medium between 12 and 36 h of culture. Two of the chains comigrated on sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis (SDS-PAGE) with radiolabeled type IV procollagen (PC) chains isolated from adult rat lung (Mr = 185,000 and 170,000 after reduction) and were coprecipitated with monospecific antibodies to type IV collagen. Cyanogen bromide (CNBr) peptide maps of the chromatographically purified chains were identical to maps of rat lung type IV PC, and confirmed the identity of these chains as pro alpha 1(IV) and pro alpha 2(IV). Type IV PC was the major high molecular weight collagen in the cell layer, and a fraction of the newly synthesized type IV PC was selectively deposited on the substratum together with newly synthesized fibronectin. Type II cells also secreted a low molecular weight, non-disulfide-bonded, collagenase-sensitive protein (Mr = 19,000, collagen standards; Mr = 26,000, globular standards). The protein coeluted with type IV PC from DEAE-cellulose but was resolved from native type IV on CM-cellulose. The protein was not precipitated with polyclonal antibodies to type IV collagen or rat surfactant apoprotein. These studies further demonstrate the heterogeneity of collagenous macro-molecules synthesized by lung epithelial cells in vitro. We suggest that interactions between pneumocyte-derived fibronectin and type IV procollagen contribute to the formation of the epithelial basement membrane and to the attachment of these cells in normal or injured lung.
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PMID:Synthesis of collagenous proteins by pulmonary type II epithelial cells. 357 11

Type V collagen was prepared from acetic acid extracts of lathyritic chick bone. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the extracted material demonstrated two collagenous bands of slower mobility than pepsin-extracted alpha 1(V) and alpha 2(V) chains. Cyanogen bromide peptide maps of these protein bands identified them as forms of alpha 1(V) and alpha 2(V). Segment long spacing (SLS) crystallite banding patterns of the acid-extracted Type V were identical within the triple-helical domain to the SLS banding patterns of pepsin-extracted Type V collagen, supporting the identification of this material. A globular domain at one end of the triple helix of the acid-extracted Type V was visualized by both rotary shadowing and negative staining of SLS crystallites. The molecular weights of the globular terminal peptides were 18,000 and 29,000, respectively, for alpha 1(V) and alpha 2(V), as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis after bacterial collagenase digestion of the isolated alpha chains. The results presented here indicate that fully processed Type V collagen in chick bone exists as a higher molecular weight form than that from pepsin extracts and retains a globular domain at one end of the triple helix. This is in contrast to the interstitial collagens in which only very small non-triple-helical domains (telopeptides) are retained in the fully processed molecules. In vitro aggregation studies demonstrated the intact fully processed form of Type V collagen forms uniform small-diameter fibrous structures. These results suggest that Type V collagen may be present in fibrous structures within tissues.
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PMID:Characterization of the tissue form of type V collagen from chick bone. 396 62

Recessive dystrophic epidermolysis bullosa, a genodermatosis characterized by dermolytic blister formation in response to minor trauma, is characterized by an incresaed collagenase synthesis by skin fibroblasts in culture. Since preliminary studies of partially purified recessive dystrophic epidermolysis bullosa collagenase suggested that the protein itself was aberrant, efforts were made to purify this enzyme to homogeneity, so that detailed biochemical and immunologic comparisons could be made with normal human skin fibroblast collagenase. Recessive dystrophic epidermolysis bullosa skin fibroblasts obtained from a patient documented to have increased synthesis of the enzyme were grown in large scale tissue culture and both serum-free and serum-containing medium collected as a source of collagenase. The recessive dystrophic epidermolysis bullosa collagenase was purified to electrophoretic homogeneity using a combination of salt precipitation, ion-exchange, and gel-filtration chromatography. In contrast to the normal enzyme, the recessive dystrophic epidermolysis bullosa collagenase bound to carboxymethyl-cellulose at Ca(2+) concentrations at least 10 times higher than those used with the normal enzyme. Additionally, this enzyme was significantly more labile to chromatographic manipulations, particularly when serum-free medium was used. However, rapid purification from serum-containing medium yielded a preparation enzymatically equivalent to normal human skin collagenase. Like the normal enzyme, the recessive dystrophic epidermolysis bullosa collagenase was secreted as a set of two closely related zymogens of approximately 60,000 and approximately 55,000 daltons that could be activated by trypsin to form enzymically active species of approximately 50,000 and approximately 45,000 daltons, respectively. Amino acid analysis suggested slight variations between the normal and recessive dystrophic epidermolysis bullosa collagenases. Cyanogen bromide digests demonstrated peptides unique to the enzyme from each source. The recessive dystrophic epidermolysis bullosa proenzyme was significantly more thermolabile at 60 degrees C than the normal, a finding that correlated with an approximate fourfold decrease in the affinity of the mutant enzyme for Ca(2+), a known activator and stabilizer of human skin collagenase. Aside from the altered affinity for this metal cofactor, kinetic analysis of the structurally altered recessive dystrophic epidermolysis bullosa collagenase revealed that its reaction rates and substrate specificity for human collagen types I-V were identical to those for the normal enzyme. Likewise, enzymes from both sources displayed identical energies of activation and deuterium isotope effects. Antisera were raised to the normal and putatively mutant procollagenases respectively, and, although they displayed a reaction of identity in double diffusion analysis, immunologic differences were present in enzyme inhibition and quantitative precipitation studies. These studies indicate that recessive dystrophic epidermolysis bullosa is characterized by the increased synthesis of an enzymically normal, but structurally aberrant, collagenase.
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PMID:Human skin collagenase in recessive dystrophic epidermolysis bullosa. Purification of a mutant enzyme from fibroblast cultures. 628 34

A disulfide-cross-linked collagen has been extracted with neutral salt solutions from organ cultures of embryonic chick sternal cartilage. This collagen, which we term pM collagen, is presumed to be the native extracellular precursor molecule to disulfide-cross-linked collagen fragments recently described. Cleavage of pM collagen under native conditions with pepsin gives rise to the collagen fragments M1 and M2, which had also been isolated from pepsin extracts of chick hyaline cartilage [K. von der Mark, M. van Menxel & H. Wiedemann (1982) Eur. J. Biochem. 124, 57-62]. Native pM collagen was purified by DEAE-cellulose chromatography and agarose gel filtration. On agarose and following polyacrylamide gel electrophoresis, the unreduced molecule migrates with an apparent Mr of 300 000. Reduction of disulfide bridges produces two subunits with Mr 80 000 (pMa) and 60 000 (pMb) when compared with collagen standards. Cyanogen bromide cleavage of pMa and pMb, excised from dodecyl sulfate gels, resulted in different peptide maps, indicating that both components are genetically distinct polypeptide chains. The occasional appearance of the unreduced pM collagen as a doublet band on dodecyl sulfate gels and the observation that pMa and pMb occur in non-stoichiometric ratios suggests that pMa and pMb form separate native molecules, although their incorporation into a single pM molecule cannot be excluded. Native pM collagen was completely digested with bacterial collagenase, and contained hydroxyproline and proline in a ratio of 1.15:1, indicating the absence of significant non-collagenous domains. Thus it represents, despite several pepsinlabile sites, more likely a largely triplehelical, processed form of collagen rather than a procollagen-like molecule containing globular domains. Processing of pM collagen to M1 and M2 fragments or other intermediate forms was not observed in cartilage organ culture or in chondrocyte cell cultures within 18 h.
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PMID:Isolation and characterization of a precursor form of M collagen from embryonic chicken cartilage. 669 38

We report here a biochemical comparison between type 1 rat tail tendon collagen and collagen isolated from sea urchin peristome tissue. The sea urchin collagen consisted of two species of apparent mol masses, 140 and 116 kDa. Amino acid compositional analysis of the 140 and 116 kDa species revealed the presence of hydroxyproline and hydroxylysine as well as a glycine content of 28.1 mol.%. In solubility experiments the rat tail tendon collagen was found to precipitate at sodium chloride concentrations between 1 and 2 M while peristome collagen remained soluble at salt concentrations as high as 4 M. Incubation of the peristome and rat tail tendon collagen preparations with a sea urchin collagenase/gelatinase resulted in cleavage of the former but not the latter collagen. Upon heat denaturation at 60 degrees C, however, the rat tail tendon collagen served as a substrate for the gelatinase. Cyanogen bromide cleavage of rat tail and peristome collagens generated largely unique peptide maps. Collectively, these results suggest that structural differences exist between echinoderm and vertebrate type 1 collagens.
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PMID:Comparative biochemical analysis of sea urchin peristome and rat tail tendon collagen. 922 89