Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inactivation of the plasma serine-proteinase inhibitor alpha 1-antitrypsin (alpha 1-AT) by neutrophil metalloproteinases has been reported [Vissers, George, Bathurst, Brennan & Winterbourn (1987) Fed. Proc. Fed. Am. Soc. Exp. Biol. 46, 1390a; (1988) J. Clin. Invest. 82, 706-711; Desrochers & Weiss (1988) J. Clin. Invest. 81, 1646-1650]. To identify the enzyme responsible, supernatant from neutrophils stimulated with phorbol 12-myristate 13-acetate was subjected to preparative SDS/PAGE, both with and without activation of latent metalloproteinases with HgCl2. The lanes were subsequently sliced into pieces, the slices incubated with equimolar amounts of type I collagen and alpha 1-AT in the presence of HgCl2, and the reaction products separated by SDS/PAGE. With the latent supernatant, the characteristic collagen-cleavage products and cleaved alpha 1-AT were present in the same slices, corresponding to an Mr of 80,000-85,000. On treatment with HgCl2 both degradative activities underwent the same molecular-mass shift to a position corresponding to Mr 60,000-65,000. Western blots of neutrophil supernatants, using a polyclonal antibody to purified collagenase, showed Mr values of 83,000 for the latent enzyme and 63,000 for the HgCl2-activated enzyme. Neutrophil collagenase was purified to homogeneity and shown also to exist in a second latent form with Mr 70,000. When activated to the Mr-63,000 form by HgCl2 and incubated with equimolar amounts of collagen and alpha 1-AT, collagenase cleaved alpha 1-AT at almost twice the rate at which collagen was cleaved. alpha 1-AT cleavage was inhibited by 1,10-phenanthroline and by high concentrations of collagen. That the purified collagenase did not contain a contaminant proteinase such as stromelysin was indicated by inability of the preparation to cleave casein. Taken together these results lead us to conclude that neutrophil collagenase is capable of degrading alpha 1-AT. Neutrophil gelatinase also cleaved alpha 1-AT, but cleavage was slow when compared with its activity against gelatin.
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PMID:Human neutrophil collagenase cleaves alpha 1-antitrypsin. 217 52

The ability of von Willebrand factor protein (vWF) to agglutinate platelets with ristocetin depends upon the presence of its highest molecular weight multimers (HMWM) and its intact carbohydrate structure. Previously we demonstrated that the HMWM are preferentially adsorbed to purified fibrillar type I collagen. The role of the carbohydrate structure of vWF in this function has not been established. In these studies complete desialylation (greater than 95%) of the intact protein by neuraminidase did not interfere with the normal adsorption of vWF activity to type I collagen. In contrast, modification of the penultimate galactose of the desialylated protein with galactose oxidase or beta-galactosidase markedly reduced adsorption of vWF activity by collagen. Subsequent reduction of the oxidized desialylated protein with potassium borohydride completely regenerated the normal adsorption of vWF activity by collagen. Enzymatic modification of the penultimate galactose moiety of vWF resulted in a loss of the HMWM, as observed following SDS-glyoxyl agarose electrophoresis. This was in contrast to desialylated vWF, which appeared intact structurally and which predictably lost its HMWM upon exposure to collagen in a manner similar to native vWF. Therefore, the carbohydrate structure of vWF and, in particular, the penultimate galactose moiety, may be critical for vWF-collagen interactions and for the mediation of primary hemostasis.
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PMID:Critical role of the carbohydrate moiety in human von Willebrand factor protein for interactions with type I collagen. 230 Sep 25

A novel type IV collagen-degrading metalloproteinase was purified from the conditioned media of a murine metastatic sarcoma cell line. The molecular weight of the purified enzyme was determined to be 100 kDa by SDS-PAGE, while 700 kDa by gel filtration suggesting that the enzyme has a multimer structure. This enzyme degrades type IV collagen, but neither type I collagen nor casein. The failure of trypsin treatment to enhance the enzyme activity suggested that the purified enzyme did not require activation. Although the enzyme seems to be classified as a matrix metalloproteinase, it was inhibited by neither tissue inhibitor of metalloproteinases (TIMP) nor TIMP-2 and thus represents a novel type IV collagen-degrading metalloproteinase.
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PMID:A novel TIMP-insensitive type IV collagen-degrading metalloproteinase from murine metastatic sarcoma cells. 238 70

Previous studies have shown that a glycoprotein of Mr 47,000 (designated Gp47) is a major biosynthetic product of retinal endothelial cells in vitro (Canfield, Schor, West, Schor & Grant (1987) Biochem. J. 246, 121-129). We now present data indicating that (a) an identical protein is secreted by bovine retinal pericytes, (b) this protein is plasminogen activator inhibitor-type I (PAI-1), as revealed by immunoprecipitation with specific antibodies and reverse fibrin zymography, and (c) retinal endothelial cells and pericytes synthesize different species of matrix macromolecules, that is: type IV collagen is the major collagen secreted by endothelial cells, whereas pericytes produce predominantly type I collagen; fibronectin and thrombospondin are synthesized by both cell types. Our studies also indicate that PAI-1 is produced, albeit at considerably lower levels, by large vessel vascular cells (aortic endothelial and smooth muscle cells) and human skin fibroblasts. PAI-1 produced by human skin fibroblasts appears to be a distinct molecular species compared to its bovine counterpart as assessed by its slower mobility on SDS/polyacrylamide-gel electrophoresis. The potential significance of elevated PAI-1 production by retinal endothelial cells and pericytes, as well as their distinctive patterns of matrix biosynthesis, is discussed in terms of the involvement of these cells in the maintenance and remodelling of microvessel basement membrane.
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PMID:Plasminogen activator inhibitor-type I is a major biosynthetic product of retinal microvascular endothelial cells and pericytes in culture. 249 39

Gelatinases have been purified from the exudate in the chronic-phase (day 7) of carrageenin-induced inflammation in rats. The day-7 exudate gelatinases gave two peaks on Sephadex G-150 gel filtration, the initial step of the purification. The molecular weights of the gelatinases corresponding to the two peaks were about 300 kDa (HMW fraction) and about 110 kDa (LMW fraction), respectively. The gelatinase in the HMW fraction has been purified to homogeneity; the purified gelatinase gave a single band corresponding to a molecular weight of 57 kDa on both SDS-polyacrylamide gel electrophoresis (PAGE) and SDS-gelatin PAGE. On the other hand, the gelatinase purified from the LMW fraction was found to consist of three species, with molecular weights of 66, 64, and 57 kDa, as judged on SDS-gelatin PAGE. Granulation tissue-derived fibroblasts in culture mainly produced the 64-kDa species, which was converted to a 57-kDa species on treatment with 4-amino-phenylmercuric acetate, while rat macrophages and polymorphonuclear leukocytes mainly secreted the 96-kDa species. These results suggest that exudate gelatinases are largely produced by fibroblasts in granulation tissue and that they bind to exudate proteins, resulting in the formation of complexes with molecular weights of about 300 kDa and about 110 kDa. The gelatinases purified from the HMW and LMW fractions are metalloproteinases, as judged from the results of inhibitor experiments. Both the gelatinases degraded gelatin, but showed to proteolytic activity toward alpha-casein or type I collagen. Type IV collagen was degraded at 35 degrees C by the gelatinases purified from the LMW fraction but not by that from the HMW fraction.
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PMID:Purification and characterization of exudate gelatinases in the chronic-phase of carrageenin-induced inflammation in rats. 254 59

Bone morphogenetic protein (BMP) was extracted from the bovine bone matrix and purified by liquid chromatography. The molecular weight of the BMP was 18 kDa by SDS-PAGE, and its pI value was 4.9. Amino acid analysis suggested that the BMP is a polypeptide containing 163 amino acids. In the present study, telopeptide-free type I collagen was used as a carrier of BMP.
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PMID:Purification of bone morphogenetic protein derived from bovine bone matrix. 259 48

A positive family history is considered a risk factor for osteoporosis (OP) although the genetic or biochemical basis for this relationship remains undefined. Various mutations affecting normal synthesis of type I collagen have been reported in osteogenesis imperfecta (OI), a heritable disorder of connective tissue. Family A, in which the proband and a daughter are afflicted with OP and idiopathic scoliosis was examined for defects in collagen metabolism. Dermal fibroblast cultures were established to investigate de novo collagen synthesis. SDS-PAGE revealed an abnormally migrating alpha 2(I) chain and procollagen in two generations. Examination of the kinetics of type I collagen pC & N-propeptide processing demonstrated a rate 2x control in the proband. The phenotype family A is not OI. It shares features with families B & C, having familial clustering of OP. However, collagen synthesis was not abnormal in family B & C. These data suggest that in family A the alpha 2(I) structural defect may be related to defective skeletal matrix formation.
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PMID:Osteoporosis and familial idiopathic scoliosis: association with an abnormal alpha 2(I) collagen. 260 36

Cultured neonatal rat calvaria produce latent metalloproteases capable of degrading collagen, gelatin, and osteonectin. The osteonectin-degrading activity was further characterized and found to be optimally active between pH 6 and 8 and inhibited with EDTA and 1, 10-phenanthroline but not phenylmethylsulfonyl fluoride. Analysis of the degradation products of osteonectin by SDS-PAGE in the presence of dithiothreitol showed the generation of a somewhat stable 32,000 mw cleavage product. Comparison of the binding properties of this cleavage product with intact osteonectin indicated that the fragment retained its ability to bind hydroxyapatite in the presence of high salt (2 M NaCl). Importantly, the binding of osteonectin to type I collagen fibrils was enhanced by limited proteolysis.
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PMID:The partial degradation of osteonectin by a bone-derived metalloprotease enhances binding to type I collagen. 261 22

Two cyanogen bromide fragments (alpha 1-CB7 and alpha 1-CB8) of bovine corneal stromal collagen have been isolated and characterized. These added to those characterized in our previous work account for 95% of the amino acid sequence of the alpha 1(1)-chain. The hydroxylysine glycoside content of each fragment was determined and in this way the general distribution of glycoside over the entire molecule was deduced accounting for all the galactosylhydroxylysine and most of the glucosylgalactosylhydroxylysine of this heavily glycosylated type I collagen. The characterization of fragments alpha 1-CB7 and alpha 1-CB8 has enabled us to resolve the controversy over the relative mobilities of these fragments on SDS gels. Fragment alpha 1-CB7 of bovine corneal collagen was digested by trypsin and by staphylococcal proteinase V8. The resultant peptides were isolated by gel and ion-exchange chromatography and identified in relation to the known amino acid sequence of type I collagen. The hydroxylysine glycosides were determined in the relevant peptides providing a complete account of their distribution along this part of the collagen molecule. Most of the glycoside was found in the gap region of collagen especially near the edges of the axial holes where it could act as a peg to facilitate fibre formation. In addition, some glycoside was found in the overlap region where, being unable to fit into axial holes, it might impede the growth of the fibre and, with other glycoside of the overlap region, might be responsible for the narrow fibres of corneal collagen that are essential for corneal transparency. This glycoside, with that previously found in the peptide alpha 1-CB3 is the only hydroxylysine glycoside identified in the overlap region of a type I collagen.
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PMID:Pinpointing the sites of hydroxylysine glycosides in peptide alpha 1-CB7 of bovine corneal collagen, and their possible role in determining fibril diameter and thus transparency. 275 43

Cells released by sequential enzymatic digestion of 18-day chick calvariae were cultured over a 4-5 week period in Alpha modified Eagles medium. In some cultures the medium was supplemented with ascorbate and/or Na-beta-glycerophosphate. Microscopic examination of these cultures showed both polygonal and spindle-shaped cells. The biochemical nature of these cells was investigated by incubating the cultures with radiolabelled proline and subsequently analysing the medium and cell layer proteins by SDS/PAGE and fluorography. Osteoblast and chondrocyte-containing cultures were clearly distinguished in this way as the former cells secreted type I collagen while the latter secreted types II and X collagens as the major medium macromolecules. Type X collagen synthesis occurred after 14 days, but only in cultures supplemented with both ascorbate and Na-beta-glycerophosphate, and was maintained for the duration of the culture period. Unsupplemented cultures and those containing either ascorbate alone or Na-beta-glycerophosphate alone failed to synthesize type X collagen after 28 days. Isolated cells pulsed with radiolabelled proline at confluence and organ cultures of embryonic chick calvaria synthesized types I and V collagens only. These data demonstrate that the expression of phenotype by heterogeneous populations of bone cells could be modulated by a combination of culture conditions including the length of time in culture and conditions favourable for the formation of a mineralized matrix.
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PMID:Expression of the chondrogenic phenotype by mineralizing cultures of embryonic chick calvarial bone cells. 276 13


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