Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.2.2.7 (heparinase)
 1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Different cell types within developing chick skeletal muscle were assayed for their ability to release factors into culture media which could affect the survival and neuritic development of labelled motoneurones and lateral motor column explants. Enriched cultures of myotubes, myoblasts, fibroblasts and mesenchyme were prepared by selective preplating and trypsinisation techniques. Degrees of enrichment were assessed immunofluorescently and morphologically; fibroblasts were the main contaminating cell type. Medium conditioned over each cell type was then tested in dose-response assay against both explants and dissociated motoneurones. In both cases the myotube conditioned medium (MCM) promoted the greatest levels of both survival and neuritic outgrowth, and had the greatest relative potency of all of the cell types. When MCM was preincubated over polycationic substrata, it lost the ability to promote neuritic growth; this could be restored if fresh conditioned medium (CM) was added to the cultures. Thus it was demonstrated that within the MCM there are physically separable agents responsible for neurone survival and neurite expression. The neurite-promoting factor (NPF) within the MCM was stable to collagenase, deoxyribonuclease, neuraminidase and chondroitinase ABC, but was destroyed by trypsin and heparinase. These results imply that a heparan sulfate proteoglycan is essential for the activity of the factor.
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PMID:Motoneurone survival and neuritic outgrowth promoted by different cell types in embryonic muscle. 402 82

Rat sympathetic neurons, plated onto extracellular matrix produced by cultured bovine corneal endothelial cells, rapidly extended neurites in the absence of nerve growth factor (NGF). The response was unaffected by antiserum to NGF. Rapid outgrowth also occurred when sympathetic neurons were plated onto polylysine-coated surfaces that had been exposed to serum-free medium conditioned by corneal endothelial cells (CMSF). A response was seen even when the neurons were cultured without serum. When plated onto a polylysine-coated dish treated with CMSF over half its surface, only the neurons on the treated half extended neurites. The active factor in CMSF was destroyed by trypsin, acid (pH 1.6), base (pH 12.7), or heating to 80 degrees C; it was stable to heating to 60 degrees C, collagenase, deoxyribonuclease, and neuraminidase. The factor elutes just after the void volume of a Sepharose 6B column. In associative cesium chloride gradients, it sediments as a peak centered at a density of 1.36-1.37, corresponding to a peak of material that can be biosynthetically labeled with [35S]sulfate or [3H]leucine. Material from this fraction was inactivated by heparinase, but not chondroitinase ABC, implying that a heparin sulfate proteoglycan is essential for the factor's activity. Inactivation by contaminants in the heparinase preparation was ruled out. Further purification indicated that the active factor may exist as an aggregate containing a heparin sulfate proteoglycan and other molecules. CMSF also promoted neurite outgrowth by other types of neurons. Furthermore, a variety of cell types were shown to produce factors similar to that in CMSF.
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PMID:Characterization of a factor that promotes neurite outgrowth: evidence linking activity to a heparan sulfate proteoglycan. 621 11

A collection of 50 clinical isolates of Bacteroides was examined for plasmid deoxyribonucleic acid content. An attempt was then made to correlate the presence of plasmids with a specific phenotypic property. Of the 20 Bacteroides which contained plasmids, 18 were found to harbour plasmids of less than or equal to 9.8 megadaltons. The most common plasmid had a molecular weight of 4.8 megadaltons and was found in 9 strains. Most strains had multiple plasmid bands. All strains were examined for resistance to penicillin, cefoxitin, erythromycin, tetracycline, sulphamethoxazole, clindamycin, chloramphenicol, arsenate, silver, cadmium, mercury, chromium, lead, nickel and cobalt, and for the production of beta-lactamase, heparinase, deoxyribonuclease, haemolysins and bacteriocins. Using a Chi-squared analysis, there was no statistically significant correlation between any of these phenotypic traits and the presence of plasmids, except bacteriocin production. A total of 15 out of 20 (75%) of plasmid-containing strains produced bacteriocins while only 10 out of 30 (33%) of plasmid-free strains were capable of bacteriocin production (chi 2, p less than 0.005). Attempts to transfer or cure resistance to antibiotics and heavy metals or bacteriocin production were not successful.
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PMID:Physiological properties and plasmid content of Bacteroides spp. 653 4