Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The binding of 125I-labeled thrombin to rat peritoneal macrophages isolated 20 h after the ip injection of thioglycollate broth or lipopolysaccharide decreased to 20% of the value found in resident macrophages due to a decrease in the number of receptors. The binding returned to normal values within a week after the injection. The decline parallelled more or less the Vmax for the 5'-nucleotidase activity. This decrease in the binding of thrombin could not be explained by an immigration of monocytes into the peritoneal cavity, since the binding of 125I-labeled alpha 2-macroglobulin-trypsin complex increased 4.5-fold in the same cell population due to an increase in the number of receptors, and blood monocytes do not bind alpha 2-macroglobulin-trypsin complex. The increase in the binding of alpha 2-macroglobulin-protease complex parallelled an increase in the incorporation of glucosamine, although the latter did not increase to the same extent. Engulfment of plasma membrane after phagocytosis did not result in a decreased binding of thrombin, but preincubation at 37 degrees C with concanavalin A caused a minor reduction in the binding. There was a positive correlation between the binding of alpha 2-macroglobulin-trypsin complex and the fraction of polymorphonuclear leukocytes in the peritoneal exudate and a negative correlation between the binding of thrombin and the fraction of polymorphonuclear leukocytes in the exudate, when the inflammation was induced by a milder stimulus, sterile NaCl, indicating a common signal for the polymorphonuclear leukocyte chemotaxis and the macrophage differentiation.
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PMID:In vivo inflammatory stimulation induces a transient change in the binding of thrombin to rat peritoneal macrophages. 131 45

1. The biological properties of nine venom samples from six taxa of Micrurus were investigated. The venoms exhibited low protease, phosphodiesterase and 5'-nucleotidase activities, moderate to strong phospholipase A and hyaluronidase activities, variable L-amino acid oxidase activity and were devoid of arginine ester hydrolase and thrombin-like activities. Some venom samples exhibited strong acetylcholinesterase activity. Venoms of M. c. dumerili and M. frontalis exhibited exceptionally high alkaline phosphomonoesterase activity while two of the M. f. fulvius venom samples tested exhibited strong hemorrhagic activity in mice. 2. The polyacrylamide gel electrophoretic patterns of the venoms indicate that most of the Micrurus venom proteins are basic proteins. All Micrurus venoms tested exhibited similar SDS-polyacrylamide gel electrophoretic patterns, with an intense low mol. wt protein band. 3. The Micrurus venoms appear to exhibit biological properties similar to other elapid venoms found in Asia and Africa. There are, however, no common characteristics in the biological properties of the venoms examined at the generic level.
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PMID:The biological properties of venoms of some American coral snakes (Genus micrurus). 158 85

1. The hemorrhagic, procoagulant, anticoagulant, protease, arginine ester hydrolase, phosphodiesterase, alkaline phosphomonoesterase, 5'-nucleotidase, hyaluronidase, phospholipase A and L-amino acid oxidase activities of 50 venom samples from 20 taxa of rattlesnake (genera Crotalus and Sistrurus) were examined. 2. The results show that notwithstanding individual variations in the biological activities of Crotalus venoms and the wide ranges of certain biological activities observed, there are some common characteristics at the genus and species levels. 3. The differences in biological activities of the venoms compared can be used for differentiation of the species. Particularly useful for this purpose are the thrombin-like enzyme, protease, arginine ester hydrolase, hemorrhagic and phospholipase A activities and kaolin-cephalin clotting time measurements.
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PMID:A comparative study of the biological activities of rattlesnake (genera Crotalus and Sistrurus) venoms. 167 59

1. The lethalities, anticoagulant effects, hermorrhagic, thrombin-like enzyme, hyaluronidase, protease, arginine ester hydrolase, 5'-nucleotidase, L-amino acid oxidase, alkaline phosphomonoesterase, phosphodiesterase and phospholipase A activities of twenty-three samples of venoms from twelve species of Asian lance-headed pit vipers (genus Trimeresurus) were examined. 2. The results indicate that notwithstanding individual variations in venom properties, the differences in biological properties of the Trimeresurus venoms can be used for the differentiation of venoms from different species of Trimeresurus. 3. The results also suggest that differences in the biological properties of snake venoms are useful parameters in the classification of snake species. 4. Our results indicate that venoms from the species T. okinavensis exhibited biological properties markedly different from other Trimeresurus venoms examined. This observation supports the recently proposed reclassification of T. okinavensis as a member of the genus Ovophis, rather than the genus Trimeresurus.
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PMID:A comparative study of the enzymatic and toxic properties of venoms of the Asian lance-headed pit viper (Genus Trimeresurus). 255 29

Among all the purified components from A. acutus venom, including ADPase, 5'-nucleotidase, phospholipase A2 and fibrinogenases, only the venom ADPase (50-100 micrograms/ml) shows marked inhibitory action on ADP (10 microM)-, collagen (10 micrograms/ml)- and sodium arachidonate (100 microM)-induced platelet aggregations of rabbit platelet-rich plasma. The venom 5'-nucleotidase (100 micrograms/ml) inhibited ADP-induced platelet aggregation by 31 +/- 4% (n = 4, P less than 0.05). Fibrinogenolytic enzymes (fractions I and IX, 100 micrograms/ml) did not significantly inhibit platelet aggregation induced by ADP (10 microM), collagen (10 micrograms/ml) or sodium arachidonate (100 microM). However, when the fibrinogenase (fraction IX, 100 micrograms/ml) was preincubated with platelet-rich plasma for 30 min it inhibited collagen (20 micrograms/ml)- and ADP (10 microM)-induced platelet aggregations by 34 +/- 9% (n = 4, P less than 0.05) and 35 +/- 6% (n = 4, P less than 0.05), respectively. The phospholipase A2 (100 micrograms/ml) did not affect platelet aggregation. The venom ADPase is a single chain polypeptide with a molecular weight of 94,000. The specific ADPase activity is estimated to be 4.3 mu moles Pi/min/mg of protein. It also possesses phosphodiesterase and weak 5'-nucleotidase activities.
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PMID:Platelet aggregation inhibitors from Agkistrodon acutus snake venom. 303 52

The toxic and biological activities of four samples of Trimeresurus purpureomaculatus venom were examined. The lethality, protein composition and biological activities of the four venom samples were similar. Three of the venom samples had LD50 (i.v.) values of 0.9 micrograms/g while the fourth had a lower LD50 (i.v.) of 0.45 micrograms/g. All four venom samples exhibited hemorrhagic, edema-inducing, anticoagulant and thrombin-like activities as well as the usual enzymes found in crotalid venoms. DEAE-Sephacel ion exchange chromatographic fractionation of the venom yielded 10 protein fractions. Only two fractions (fractions A and F) were lethal to mice; the major lethal fraction being fraction F. This fraction had an LD50 (i.v.) of 0.2 micrograms/g and exhibited hemorrhagic, edema-inducing and thrombin-like activity. It also exhibited phospholipase A, arginine ester hydrolase, arginine amidase, protease, 5'-nucleotidase, acetylcholinesterase and alkaline phosphomonoesterase activities. The lethal potency of fraction F is potentiated by fraction G, which exhibited anticoagulant activity as well as hemorrhagic, edema-inducing and enzymatic activities. Fractions F plus G account for almost 100% of the lethal potency of the venom.
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PMID:Biological properties of Trimeresurus purpureomaculatus (shore pit viper) venom and its fractions. 324 58

The enzyme contents of four venom samples of Calloselasma rhodostoma were analyzed. The venoms contained phosphodiesterase, alkaline phosphomonoesterase, 5'-nucleotidase, protease, phospholipase A, L-amino acid oxidase, hyaluronidase, arginine ester hydrolase, arginine amidase, fibrinogenase and coagulant enzyme activities. There is significant variation in the contents of coagulant enzyme, arginine ester hydrolase, hyaluronidase, protease, phosphodiesterase, alkaline phosphomonoesterase and L-amino acid oxidase. DEAE-Sephacel ion exchange chromatography of the venom resolved it into eight major protein fractions. The eight fractions were heterogeneous and exhibited more than one type of enzymatic activity. The 5'-nucleotidase, alkaline phosphomonoesterase, protease, coagulant enzyme, arginine ester hydrolase, arginine amidase and fibrinogenase exist in multiple forms.
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PMID:Enzymatic activities of Calloselasma rhodostoma (Malayan pit viper) venom. 375 Mar 51

Viable and homogeneous endothelial cells were obtained from isolated guinea pig hearts by application of a special perfusion technique of the coronary system with an isotonic collagenase-trypsin solution and subsequent purification of the dissociated cells by Percoll density gradient centrifugation. The coronary endothelial cells were grown in tissue culture for periods up to 7 months. Serial passage proved to be possible. During logarithmic growth, generation time was found to be 18 h; it could be reduced to 16 h by addition of thrombin to the culture medium. Light, phase contrast and scanning electron microscopy as well as autoradiography revealed that cultured coronary endothelial cells grew as strict monolayers of closely apposed, polygonal large cells. By scanning electron microscopy, it could be demonstrated that the morphology of the cultured cells changes characteristically during attachment of the cells to their substratum. The changes observed were very similar to those of proliferating endothelial cells of isolated coronary vessels kept in organ culture. According to transmission electron microscopy studies, cultured coronary endothelial cells proved to contain only an extremely small number of Weibel-Palade bodies. Nucleoside phosphorylase (EC 2.4.2.5.) and 5'-nucleotidase (EC 3.1.3.5.) were identified in freshly isolated as well as in cultured endothelial cells. Their specific and total activities proved to be much higher than in myocardial tissue, thus indicating a prominent role of nucleotide metabolism in the coronary endothelium.
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PMID:Isolation, identification, and continuous culture of coronary endothelial cells from guinea pig hearts. 728 45

The Malayan pit viper (Calloselasma rhodostoma) is of major clinical significance both as a leading cause of snakebite and as the source of ancrod (Arvin). Although its venom has been extensively studied, the degree to which venom composition varies between individuals is poorly known. We individually analysed the venoms of over 100 C. rhodostoma using isoelectric focusing. In all populations, females produced an intense band that was absent from all males, and significant ontogenetic variation was detected. Principal components analysis of the banding profiles also revealed strong geographic variation, which was significantly congruent with variation in the biological activities of the venom (phosphodiesterase, alkalinephosphoesterase, L-amino acid oxidase, arginine ester hydrolase, 5'-nucleotidase, thrombin-like enzyme, haemorrhagic activity). Studies of captive-bred snakes indicate that the intraspecific variation in venom is genetically inherited rather than environmentally induced. The intraspecific variation in venom composition and biological activity could be of applied importance to snakebite therapy, both in correct diagnosis of the source of envenomation and in the development of a more effective antivenom. Greater attention should be given to the source of C. rhodostoma venom used in research to ensure reproducibility of results.
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PMID:Electrophoretic profiles and biological activities: intraspecific variation in the venom of the Malayan pit viper (Calloselasma rhodostoma) 1007 60

By means of CM-Sephadex C-25, DEAE-Sephadex A-50, Sephadex G-200, and Sephadex G-75 chromatographies, a lupus anticoagulant like protein (LALP) from Agkistrodon halys brevicaudus was purified. On SDS-PAGE, the purified LALP had a molecular weight of 25,500 daltons under non-reducing condition and 15,000 daltons under reducing condition. The isoelectric point was pH 5.6. Its N terminal amino acid sequencing revealed a mixture of 2 sequences: DCP(P/S)(D/G)WSSYEGH(C/R)(Q/K). It was devoid of phospholipase A, fibrino(geno)lytic, 5'-nucleotidase, L-amino acid oxidase, phosphomonoesterase, phosphodiesterase and thrombin-like activities, which were found in crude venom. In the presence of LALP, PT, aPTT, and dRVVT of human plasma were markedly prolonged and its effects were concentration-dependent but time-independent. The inhibitory effect of LALP on the plasma clotting time was enhanced by decreasing phospholipid concentration in TTI test. The individual clotting factor activity was not affected by LALP when higher dilutions of LALP-plasma mixture were used for assay. Russell's viper venom time was shortened when high phospholipid confirmatory reagent was used. Therefore, the protein has lupus anticoagulant property.
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PMID:Purification and characterization of lupus anticoagulant like protein from Agkistrodon halys brevicaudus venom. 897 23


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