Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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 release of plasma-membrane-bound enzymes by phosphatidylinositol-specific phospholipase C obtained from Bacillus thuringiensis was investigated. Among the ectoenzymes of plasma membrane tested, alkaline phosphodiesterase I was released markedly from rat kidney cortex slices, in addition to alkaline phosphatase and 5'-nucleotidase. Other membrane-bound enzymes; alanine aminopeptidase, leucine aminopeptidase, dipeptidyl peptidase, leucine aminopeptidase, dipeptidyl peptidase IV, esterase and gamma-glutamyl transpeptidase could not be liberated from the treated slices. Alkaline phosphodiesterase I was released linearly from rat kidney slices with the concentration of phosphatidylinositol-specific phospholipase C, but little enzyme was released from rat liver slices. Alkaline phosphodiesterase I separated from kidney tissue with n-butanol still retained phosphatidylinositol and was transformed into a lower molecular weight form by phosphatidylinositol-specific phospholipase C. This suggests an important function for phosphatidylinositol in the binding of alkaline phosphodiesterase I to the plasma membrane of rat kidney cells. The alkaline phosphodiesterase I released from rat kidney had a molecular weight of about 240,000 and an isoelectric point (pI) of 5.4. The enzyme hydrolyzed the phosphodiester linkage of p-nitrophenyl-thymidine 5'-monophosphate at pH 8.9 and had a Km value of 0.3 mM. The enzyme was activated by Mg2+ and Ca2+, but was inhibited by EDTA. Strong inhibition took place on the addition of adenosine 5'-phosphosulfate or the nucleotide pyrophosphates, i.e., UDP-galactose and alpha, beta-methylene ATP.
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PMID:Release of alkaline phosphodiesterase I from rat kidney plasma membrane produced by the phosphatidylinositol-specific phospholipase C of Bacillus thuringiensis. 609 28

The gamma-glutamyltransferase (gamma-GT) activity decreased by 50% following adrenalectomy of female rats, in homogenate as well as in a purified plasma membrane preparation from liver. In contrast, such a variation was not found in the kidney. None of 3 other enzyme activities of the plasma membrane, namely 5'-nucleotidase, alkaline phosphatase, and alkaline phosphodiesterase I, was decreased by adrenalectomy. Administration of hydrocortisone (5 mg/100 g body weight) resulted in a 2.6-fold increase in hepatic gamma-GT activity from adrenalectomized rats. The hydrocortisone-mediated stimulation of gamma-GT activity was dose- and time-dependent. The 5'-nucleotidase and leucine aminopeptidase activities were not modified by the hydrocortisone treatment. The activity of gamma-GT was mainly associated with nuclear fractions (nuclei and plasma membranes) obtained from liver homogenates of either control, adrenalectomized or adrenalectomized hydrocortisone-treated animals, and this activity was purified 18-fold in a plasma-membrane preparation as compared to homogenate. These data suggest that adrenalectomy and conversely hydrocortisone treatment modulate specifically the hepatic plasma-membrane gamma-GT activity. This represents one of the first demonstrations of a specific modulation by glucocorticoids of an enzyme activity typical of the plasma membrane.
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PMID:In vivo modulation of rat hepatic gamma-glutamyltransferase activity by glucocorticoids. 610 52

Liver metastases due to the more common neoplastic diseases such as colorectal, breast, or bronchogenic carcinoma are a frequent occurrence and are associated with an ominous prognosis. Earlier detection followed by appropriate therapeutic interventions might have a decided effect on the subsequent course of disease. Controversy exists over the selection of tests with the greatest sensitivity, specificity, and potential utility. Preliminary evidence suggest that gamma-glutamyl transpeptidase and 5'-nucleotidase may be of particular significance. Four enzymes--gamma-glutamyl transpeptidase, 5'-nucleotidase, leucine aminopeptidase, and alkaline phosphatase plus carcinoembryonic antigen--were compared in the same blood samples from selected patients with breast and small cell carcinoma of the lung. Gamma-Glutamyl transpeptidase was the most sensitive test with 28/29 (97%) patients with hepatic metastases having elevated enzymatic activity in their sera. For patients with small cell carcinoma of the lung followed serially, gamma-glutamyl transpeptidase activity was increased an average of 5 months before liver metastases were detected by clinical means. Two factors are important in the interpretation of the results of gamma-glutamyl transpeptidase analysis: (1) Hepatic dysfunction due to diseases other than metastatic tumor involvement can cause a rise in enzyme levels as can (2) medications or ethanol which activate the hepatic microsomal drug metabolizing system. Of particular importance, however, is the fact that antitumor chemotherapy, even intensive and multiple agent, did not appear to effect the enzyme activity in the sera of patients with breast or small cell carcinoma of the lung. Gamma-glutamyl transpeptidase in combination with carcinoembryonic antigen may be of particular value in detecting liver metastases and in assessing subsequent response to therapy.
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PMID:Biological markers as an aid in the clinical management of patients with liver metastases. 612 62

The phenotype of three ectoenzymes was determined for murine resident peritoneal macrophages, macrophages elicited in vivo by treatment of mice with thioglycollate, Corynebacterium parvum or pyran, and for resident macrophages activated in vitro by treatment with lymphokine. The relationship of these biochemical markers to macrophage antiviral and anti-tumor activity was established. Thioglycollate-elicited macrophages showed a unique ectoenzyme phenotype, with increased leucine aminopeptidase and alkaline phosphodiesterase I activity and markedly reduced 5'-nucleotidase activity as compared with resident macrophages. Thioglycollate-elicited macrophages exhibited extrinsic antiviral activity against herpes simplex virus but did not show anti-tumor activity. Another ectoenzyme phenotype was shared by macrophages elicited in vivo by treatment of mice with the immunomodulators or in vitro by treatment with antigen-specific lymphokine. These macrophage populations showed increased levels of leucine aminopeptidase but reduced levels of both 5'-nucleotidase and alkaline phosphodiesterase. This ectoenzyme phenotype was associated with the acquisition by the macrophages of selective anti-tumor activity. There appear to be clear distinctions in biochemical markers and functional properties among macrophages activated by different mechanisms.
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PMID:Changes in macrophage ectoenzymes associated with anti-tumor activity. 625 Nov 33

Intact polymorphonuclear neutrophils were modified chemically by a poorly permeable reagent, diazotized sulfanilic acid, and the changes in the activity of 5'-nucleotidase, alkaline phosphodiesterase, and leucine aminopeptidase were examined. Among three plasma membrane enzymes, 5'-nucleotidase activity was hardly detected in the human neutrophils. The activity of alkaline phosphodiesterase was observed in all the neutrophils examined, but was not inhibited by diazotized sulfanilic acid in the guinea-pig neutrophils. On the other hand, the activity of leucine aminopeptidase was not only found but also inhibited by diazotized sulfanilic acid without the inhibition of lactate dehydrogenase, a cytosol enzyme, in all the neutrophils, suggesting that leucine aminopeptidase is located generally on the plasma membrane as an ecto-enzyme in the neutrophils.
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PMID:Leucine aminopeptidase as an echo-enzyme of polymorphonuclear neutrophils. 625 75

High voltage free flow electrophoresis has been applied to the separation of human platelet membranes. After short treatment with neuraminidase at the whole cell level, three membrane vesicle subpopulations have been isolated. Using a surface label (125I-labeled Lens culinaris lectin), the marker enzyme NADH-cytochrome c reductase, and lipid analysis, two of the fractions have been identified as of surface origin and the other consists of intracellular membrane elements. The distribution of adenylate cyclase, leucyl aminopeptidase, 5'-nucleotidase and Ca2+-ATPase has also been investigated, and their usefulness as markers for the different membrane fractions has been evaluated. All three fractions are vesicular but differ in size and character. Their phospholipid and cholesterol contents have been determined, and the cholesterol/phospholipid ratios of the two surface fractions are over twice that of the intracellular membrane, which also has a significantly lower microviscosity as determined by fluorescence polarization using diphenyl hexatriene. The polypeptide profiles from sodium dodecyl sulfate-polyacrylamide gel electrophoresis are particularly distinctive, with actin present in the two surface membrane fractions and absent from the intracellular membranes. Myosin, confirmed by its ATPase characteristics, is almost exclusively localized in one of the surface membrane fractions, and actin-binding protein is a prominent feature of the other.
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PMID:Characterization of human platelet surface and intracellular membranes isolated by free flow electrophoresis. 626 Jul 85

Preparations of isolated brush border plasma membrane of Hymenolepis diminuta and H. microstoma possess the following enzymatic activities: alkaline phosphohydrolase (E.C. 3.1.3.1); Type I phosphodiesterase (E.E. 3.1.4.1); ribonuclease (E.C. 3.1.4.22); adenosine triphosphatase (E.C. 3.6.1.3); and 5'-nucleotidase (E.C. 3.1.3.5). The following enzymatic activities could not be demonstrated in either membrane preparation: Type II phosphodiesterase (E.C. 3.1.4.18); cyclic adenosine-3', 5'-monophosphate phosphodiesterase (E.C. 3.1.4.17); leucine aminopeptidase (E.C. 3.4.11.1); maltase (alpha-glucosidase; E.C. 3.2.1.20); and lactase (beta-galactosidase; E.C. 3.2.1.23). These data generally agree with those of previous studies in which similar membrane-bound enzymes were demonstrated in intact (living) worms.
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PMID:A comparison of membrane-bound enzymes of the isolated brush border plasma membranes of the cestodes of Hymenolepis diminuta and H. microstoma. 628 Jan 22

Previous immunolabeling studies (Roman, L.M., and A.L. Hubbard, 1983, J. Cell Biol., 96:1548-1558; Roman, L.M., and A.L. Hubbard, 1984, J. Cell Biol., 98:1488-1496, companion paper) established leucine aminopeptidase (LAP) as a specific marker for the bile canalicular (BC) domain of the rat hepatocyte plasma membrane (PM). In this study, we have isolated membrane from a sonicated PM vesicle fraction using anti-LAP-coated Staphylococcus aureus cells as a solid-phase immunoadsorbent. The extent and specificity of the immunoadsorption were assessed by following the behavior of LAP (the BC marker) and 32P-labeled membrane phospholipids (a uniform membrane marker). The BC fraction obtained was significantly enriched in LAP (yield: greater than 70% of PM-LAP). Alkaline phosphatase, 5'-nucleotidase, and a 110,000-dalton glycoprotein, HA-4, were enriched in the BC fraction to the same extent as LAP (enzyme or antigen/LAP = 1.0). However, alkaline phosphodiesterase I was not enriched to the same degree (enzyme/LAP = 0.5). Contamination of this BC fraction by membrane derived from the sinusoidal domain and endoplasmic reticulum, as determined from the distribution of the asialoglycoprotein receptor and NADH cytochrome c reductase, respectively, was small (less than 13%).
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PMID:A domain-specific marker for the hepatocyte plasma membrane. III. Isolation of bile canalicular membrane by immunoadsorption. 637 Oct 22

Macrophages have been obtained from the peritoneal cavities of C57BL/6 mice following treatment with C. parvum, MVE-2, mineral oil, or thioglycollate. Cell populations were primarily composed of mononuclear phagocytes as determined by a latex bead uptake assay. Macrophages obtained from C. parvum or MVE-2 were activated as judged by enhanced cytostatic activity against two tumor cell target lines. Thioglycollate-elicited macrophages demonstrated much lower cytostatic ability. Rats were immunized with activated MVE-2 macrophages. Hybridomas were prepared by fusion with a non-secreting myeloma cell line followed by cloning. Cell supernates were selected on the basis of binding to activated but not elicited macrophages. The monoclonal antibody produced has been characterized by flow cytometry. The antibody does not react with syngeneic erythrocytes, thymocytes, or spleen cells. Reaction with thioglycollate macrophages is very low. Alternatively, intense binding is found on activated macrophages. This antigen which accompanies macrophage activation for tumor cell cytostasis is designated as macrophage activation antigen-1 (MAA-1). Several important physiological changes accompany the process of macrophage activation. For example, activated macrophages demonstrate enhanced microbicidal, phagocytic, secretory, and tumoricidal activity (for reviews see refs. 1,2). Concommitant alterations in cell surface properties have been observed. These include: (a) changes in surface morphology and spreading (3-5), (b) altered lipid and protein content (6,7), (c) decreases in 5'-nucleotidase activity and alkaline phosphodiesterase (8), increases in leucine aminopeptidase (8), decreases in mannose receptors (11,12), and antigen F4/80 (11), (d) increases in Ia antigens (11,12), and (e) increased tumor cell binding (13). These structural and functional modifications indicate that activated macrophages represent a unique class of functionally differentiated cells (9). Antigenic modifications accompanying macrophage differentiation are of special interest. Markers for specific macrophage classes might be useful in defining differentiation pathways, dissecting type-specific functional activities such as tumor cytotoxicity, and providing a means to identify macrophage subsets in heterogeneous cell populations. In the present work we have taken the first step in this direction by defining a cell surface macrophage activation antigen.
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PMID:Characterization of a monoclonal antibody defining a macrophage activation-specific cell surface antigen. 674 39

The administration of the bone-seeking isotope, 89Sr, to mice results in severe monocytopenia without any apparent effect on the numbers of resident peritoneal macrophages (Mphi). An explanation for this dichotomy was sought by determining whether the residual blood monocytes were still an effective source of Mphi after 89Sr treatment. Stem cell enumeration showed that a 90% fall in bone marrow macrophage colony-forming cells after 89Sr was accompanied by a 10-fold rise in splenic M-CFC. Splenectomy performed before 89Sr treatment, however, resulted in little additional monocytopenia and had no affect on the numbers of resident peritoneal Mphi even when sampling was extended to 31 days, an interval beyond the accepted half-time for peritoneal Mphi. Intraperitoneal injections of thioglycollate or Corynebacterium parvum elicited few or no monocyte-Mphi during respective intervals of 4 and 7 days. Elicitation with thioglycollate was attempted in tritiated thymidine-labeled mice 26 days after 89Sr. Four days later only a 2-fold increase in labeled peritoneal Mphi was found in the 89Sr-treated mice compared with a 150-fold increase in the controls. Studies of the ectoenzymes 5'-nucleotidase, alkaline phosphodiesterase I, and leucine aminopeptidase in such elicitation experiments suggested that the observed changes in activities reflected the direct stimulation of resident Mphi rather than monocyte immigration. Overall, the results indicate that treatment with 89Sr distinguishes two large populations of Mphi on the basis of their dependence on bone marrow. Mphi of inflammation reflect the monocytopenia and are severely and rapidly depleted by such treatment. The maintenance of resident type Mphi, on the other hand, appears to be independent of both the state of the bone marrow and the level of monocytes in the blood.
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PMID:Differential effects of chronic monocyte depletion on macrophage populations. 688 84


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