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)

Glycosaminoglycans were isolated from purified fractions of glomerular basement membranes and partially characterized by chemical analysis and cellulose acetate electrophoresis. Basement membranes were prepared by detergent treatment of rat glomeruli and subjected to digestion with papain and Pronase. Glycosaminoglycans were isolated from the digests by precipitation with cetyl pyridinium chloride and ethanol. Results of cellulose acetate electrophoresis of the isolated glycosaminoglycan fraction revealed the presence of one major and one minor spot. The major spot was identified as heparan sulfate because it comigrated with the heparan sulfate standard and was sensitive to heparinase and to nitrous acid oxidation but insensitive to chondroitinase ABC and to testicular or leech hyaluronidase. The minor spot was tentatively identified as hyaluronic acid based on its migratory behavior and sensitivity to leech and testicular hyaluronidase. The chemical composition of the isolated glycosaminoglycan was typical of that of heparan sulfate (high carbazole/orcinol ratio, high sulfate content, absence of galactosamine). The data support and confirm the cytochemical data obtained previously [Kanwar, Y. S. & Farquhar, M. G. (1979) Proc. Natl. Acad. Sci. USA 76, 1303-1307] demonstrating that heparan sulfate is the only sulfated glycosaminoglycan detectable in the glomerular basement membrane. The present results suggest that in addition to sulfated glycosaminoglycan some nonsulfated glycosaminoglycan (hyaluronic acid) may also be present in the glomerular basement membrane.
Proc Natl Acad Sci U S A 1979 Sep
PMID:Isolation of glycosaminoglycans (heparan sulfate) from glomerular basement membranes. 15 57

The total degradation of heparin by the joint action of a purified heparinase and a heparitinase from Flavobacterium heparinum is reported. The heparinase acts directly upon heparin, yielding 52% of a trisulfated disaccharide (O-(alpha-L-ido-4-enepyranosyluronic acid 2-sulfate)-(1leads to 4)-2sulfoamino-2-deoxy-D-glucose 6-sulfate) and 40% of a tetrasaccharide besides small amounts of hexa- and disaccharides. The tetrasaccharide is in turn completely degraded by the heparitinase, forming trisulfated disaccharide and disulfated disaccharide (O-(alpha-D-glyco-4-enepyranosyluronic acid)-(1leads to 4)-2-sulfoamino-2-deoxy-D-glucose 6-sulfate) in equal amounts. These and other results indicate that the tri- and disulfated disaccharides are linked alternately, in a proportion of 3:1, respectively. The primary structure of heparin and the mode of action of the heparinase and the heparitinase are proposed based on the analysis of the different products formed by the action of the enzymes.
J Biol Chem 1975 Sep 10
PMID:Structure of heparin. Characterization of the products formed from heparin by the action of a heparinase and a heparitinase from Flavobacterium heparinum. 115 84

Heparin, in a concentration-dependent manner, inhibited the generation of conjugated dienes and thiobarbituric acid-positive substances when incubated with Fe2+ and gamma-linolenic acid. In the conjugated diene assay, other glycosaminoglycans, on a molar basis calculated with respect to their respective hydrated disaccharide repeat units, were less effective than heparin. Heparin which had been re-N-sulphonated after removal of both N-sulphonates and O-sulphates, and heparin in which iduronate residues had been reduced to idose residues, were largely unaffected in their activity. Removal of both N-sulphonates and O-sulphates greatly reduced the effectiveness of the heparin. Analysis of the effects of heparin fragments generated by heparinase I treatment of heparin showed that depolymerization decreased the effectiveness of the heparin. It is possible that heparins and related strongly acidic polysaccharides may function as endogenous antioxidants, and that sequestration by them, or harmless oxidation by them, of ions such as Fe2+, contributes to their effectiveness.
Biochem J 1992 Sep 15
PMID:Inhibition by heparin of Fe(II)-catalysed free-radical peroxidation of linolenic acid. 141 30

Org 10172 provided adequate anticoagulation for this patient. An excellent correlation between anti-factor Xa activity and ACT was observed at the doses used for CPB. If high-dose Org 10172 is used, these data suggest that it may be possible to circumvent the measurement of anti-factor Xa activity by using the ACT as an index of this heparinoid's anticoagulant effect. Because postoperative bleeding may be excessive, however, development of a method of reversal of Org 10172 is desirable. Although the optimal ACT, dose, plasma concentration, and means of reversal (e.g., protamine vs. heparinase) remains to be determined, heparinoids provide an alternate means of anticoagulation for CPB in patients unable to receive standard heparin.
Anesthesiology 1990 Sep
PMID:"Heparin-free" cardiopulmonary bypass: first reported use of heparinoid (Org 10172) to provide anticoagulation for cardiopulmonary bypass. 169 48

Basic fibroblast growth factor has multivariate effects in stimulating cell growth and the processes that surround tissue repair. Pathophysiologic studies have been hampered by the stability of the compound. Though very potent, basic fibroblast growth factor is rapidly degraded when injected or ingested. Controlled release of basic fibroblast growth factor would allow for examination of the chronic effects of this compound. Conventional matrix polymer-based release devices were fabricated and basic fibroblast growth factor released in a sustained fashion, but 99% of basic fibroblast growth factor mitogenic activity was lost. The source of these losses was identified and preventative measures examined. Preservation and stabilization of basic fibroblast growth factor was accomplished by binding the factor to heparin-Sepharose beads. This permitted prolonged storage, repeated handling, and the encapsulation of basic fibroblast growth factor within a microspherical controlled-release device using a naturally occurring polymer material, alginate. Encapsulation was accomplished with 77% efficiency and 87.5 +/- 12% of the basic fibroblast growth factor was released in a biologically active form. Release activation and regulation was achieved when cleavage of the basic fibroblast growth factor-heparin bonds was enhanced (e.g. by enzymatic bond cleavage with heparinase). Kinetic profiles were identified for a variety of experimental conditions and the effects of the controlled release of basic fibroblast growth factor on BALBc/3T3 fibroblasts examined.
Biomaterials 1991 Sep
PMID:Controlled and modulated release of basic fibroblast growth factor. 174 4

A 15 year old girl with aplastic anemia developed a heparin-like anticoagulant during the course of systemic candidiasis. This was initially detected in the laboratory by an elevation of the thrombin clotting time which corrected with toluidine blue but not by mixing with normal plasma. In vivo and in vitro the anticoagulant was remarkably resistant to neutralization by protamine sulfate. Nevertheless, its heparin-like nature was confirmed by its sensitivity to heparinase and its dependence on antithrombin III.
Am J Hematol 1990 Sep
PMID:Heparin-like anticoagulant associated with systemic candidiasis. 238 67

To gain insight into the cellular and molecular mechanisms underlying cell interactions in the early postnatal mouse cerebellum, Ca2+-dependent and -independent aggregation mechanisms were characterized using single cell suspensions under conditions that allow discrimination between the two mechanisms. When cerebellar cells were derived from newborn to 10-day-old mouse cerebellum, both mechanisms were active and showed no major change in activity during this time period. Mg2+ could not replace Ca2+ in the Ca2+-dependent mechanism. In contrast to the Ca2+-independent mechanisms, the Ca2+-dependent mechanism was inactive at low temperatures, suggesting a necessity for molecular rearrangement within the surface membrane during aggregation. Neuraminidase, chondroitinase, heparinase or hyaluronidase treatment of cells did not influence the aggregation of cells under Ca2+-dependent and -independent conditions. Chondroitin sulfate inhibited and hyaluronic acid stimulated the Ca2+-dependent mechanism, whereas chondroitin sulfate only slightly and hyaluronic acid strongly inhibited the Ca2+-independent one. Dextran sulfate slightly inhibited both mechanisms, whereas heparin and fucoidan, a complex sulfated carbohydrate, did not influence cell aggregation, while they strongly inhibited attachment of cells to laminin. The polycation poly-L-lysine slightly stimulated the Ca2+-independent mechanism, but inhibited the Ca2+-dependent one. Interestingly, chondroitin sulfate and hyaluronic acid strongly stimulated cell aggregation under conditions where both mechanisms were almost destroyed or inactive. Dextran sulfate showed only a small effect under these conditions. These observations indicate that different molecular mechanisms are active in cell-cell versus cell-extracellular matrix interactions and suggest a hitherto unknown complexity in molecular mechanisms during early postnatal cerebellar development.
Brain Res 1988 Sep 01
PMID:Characterization of Ca2+-dependent and -independent aggregation mechanisms among mouse cerebellar cells. 246 13

The activity of tissue plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) is stimulated by heparin. Heparin binds tightly to t-PA, u-PA, and plasminogen and decreases the usual stimulatory effect of fibrin on t-PA activity. In the present study we have found that low molecular weight heparin (LMW-heparin) preparations obtained by nitrous acid depolymerization or heparinase treatment of standard heparin have different properties with respect to their interaction with the fibrinolytic system. LMW-heparin prepared by either method does not stimulate plasmin formation by t-PA. However, these preparations of heparin still efficiently accelerate the inhibition of thrombin by antithrombin III. Binding data show that LMW-heparin does not bind t-PA and Glu-plasminogen and only binds very weakly to Lys-plasminogen. These results illustrate that it is possible to selectively destroy the fibrinolytic stimulating properties of heparin while leaving the classical anticoagulant characteristics intact.
J Biol Chem 1989 Sep 15
PMID:Anticoagulant low molecular weight heparin does not enhance the activation of plasminogen by tissue plasminogen activator. 250 19

Oligosaccharides prepared from glycosaminoglycans (GAGs) including heparin, heparan sulfate, chondroitin sulfates, dermatan sulfate, and keratan sulfate were analyzed using reverse-phase ion-pairing HPLC and ion-exchange HPLC with suppressed conductivity detection. The results were compared with those obtained by strong anion-exchange HPLC using uv detection. These oligosaccharides were first prepared by enzymatically depolymerizing the GAGs with enzymes including heparin lyase (EC 4.2.2.7), heparan sulfate lyase (EC 4.2.2.8), chondroitin ABC lyase (EC 4.2.2.4), and keratan sulfate hydrolase (EC 3.2.1.103). Analysis was then performed without derivitization under isocratic conditions with a limit of sensitivity in the picomole range. Preliminary studies suggest that this approach may be particularly useful in examining oligosaccharides having no uv chromophore such as those prepared from keratan sulfate.
Anal Biochem 1989 Sep
PMID:Analysis of glycosaminoglycan-derived oligosaccharides using reversed-phase ion-pairing and ion-exchange chromatography with suppressed conductivity detection. 251 May 51

Confluent cultures of human endothelial cells deposit into extracellular matrix (ECM) distinct heparan sulfate proteoglycans (HSPG) which modulate acidic fibroblast growth factor's (aFGF) ability to stimulate human endothelial cell mitogenic capacity. Extracellular matrix 35S-HSPG were isolated from cultures metabolically labelled with Na235SO4 by DEAE-Sepharose, Sepharose CL-4B, and aFGF-Affi-Gel 15 column chromatography and identified by resistance to chondroitinase ABC and sensitivity to nitrous acid. Fifty to sixty percent of the 35S-HSPG deposited into ECM do not bind aFGF. The bound 35S-HSGP (40-50% of the total counts applied) eluted from the aFGF-Affi-Gel column after the addition of buffer containing 2 M NaCl. aFGF-binding and aFGF-nonbinding 35S-HSPG were individually pooled and further purified by Sepharose CL-4B column chromatography. 35S-HSPG which bind aFGF, designated HSPGP, were 100-fold superior to heparin in augmenting the mitogenic efficacy of aFGF in sparse proliferating cultures. In contrast, however, 35S-HSPG, which did not bind aFGF, designated HSPG1, inhibited aFGF-stimulated proliferation in both sparse and subconfluent endothelial cell cultures. The majority of the biological activity of both aFGF-potentiating HSPGP and aFGF-inhibitory HSPG1 was contained in the glycosaminoglycan chains released by alkaline borohydride treatment of intact HSPGP or HSPG1, respectively. 3H-Core protein derived from HSPGP or HSPG1 contained only minor biological activity. The ability of heparitinase or heparinase (Flavobacterium heparinum) to abolish biological activity differed, depending upon the HSPG tested, also suggested that these are two distinct HSPGs.
J Cell Physiol 1989 Sep
PMID:Extracellular matrix heparan sulfate proteoglycans modulate the mitogenic capacity of acidic fibroblast growth factor. 252 52


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