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:3.1.4.1 (phosphodiesterase)
18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Highly sensitive technique are described for the assay of plasma membrane (5'-nucleotidase, alkaline phosphatase), microsomal (neutral alpha-glucosidase, leucyl-2-naphthylamidase) and biliary canalicular (gamma-glutamyltransferase) enzymes and for nine acid hydrolases (acid phosphatase, phosphodiesterase, beta-glucosidase, alpha-glucosidase, alpha-galactosidase, beta-galactosidase, alpha-mannosidase, N-acetyl-beta-glucosaminidase, beta-glucuronidase) in human liver. 2. Optimum and specific assay systems have been developed which give linear kinetics for all enzymes. 3. The range of enzyme activities in samples of human liver, obtained by closed needle biopsy, and sera have been determined.
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PMID:Enzyme activities in human liver biopsies: assay methods and activities of some lysosomal and membrane-bound enzymes in control tissue and serum. 1 4

The trypanocidal drug suramin is known to concentrate in lysosomes and to depress the activity of different lysosomal enzymes. We have previously shown that suramin can inhibit the activity of the islet lysosomal enzyme acid amyloglucosidase, a glycogenolytic glucose-producing hydrolase, which seems to be involved in certain insulin-secretory processes. In the present investigation we studied the pH dependency and dose-response effects of suramin on islet lysosomal enzyme activities as well as the effect of suramin treatment on the insulin-secretory response to various secretagogues in mice. It was found that two injections of suramin (0.18 mmol/kg) to normal NMRI mice at -24 and -2 h induced a moderate depression of the activities of islet acid amyloglucosidase (-22%) and acid phosphatase (-13%), whereas no effect was recorded for the activities of acid alpha-glucosidase, N-acetyl-beta-D-glucosaminidase and the non-lysosomal enzyme neutral alpha-glucosidase. Direct addition of different concentrations of suramin to islet homogenates showed that the drug was a potent inhibitor of acid amyloglucosidase and acid alpha-glucosidase at pH 4.0. At pH 5.0, suramin induced a large increase in acid alpha-glucosidase activity, whereas acid amyloglucosidase and acid phosphatase were inhibited. Suramin-injected mice showed a reduced insulin-secretory response to the sulphonylurea drug glibenclamide (-45%), whereas the insulin response to the cholinergic agonist carbachol or the phosphodiesterase inhibitor IBMX (1-isobutyl-3-methylxanthine) was unaffected. It is concluded that suramin inhibits islet acid amyloglucosidase activity in vivo and in vitro, whereas its effect on acid alpha-glucosidase is complex and pH dependent.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of the lysosomotropic drug suramin on islet lysosomal enzyme activities and the insulin-secretory response induced by various secretagogues. 172 7

Phosphoglycans from the cell wall of many strains of Streptococci contain terminal carbohydrate units linked by phosphodiester bridges to other residues of the glycans. In the immune response to phosphoglycans, the terminal carbohydrate-phosphate moieties function as antigenic determinants and induce the synthesis of antibodies with specificity for the glycosyl-phosphoryl units. It has now been found that such terminal carbohydrate units can be removed by treatment of the glycans with appropriate glycosidases. Thus, an almond beta-glucosidase releases glucose from a streptococcal Group D phosphoglycan with beta-glucosyl phosphate units, a jack bean N-acetyl-beta-glucosaminidase releases N-acetylglucosamine from a streptococcal Group L phosphoglycan with N-acetyl-beta-glucosaminyl phosphate units, and a rice alpha-glucosidase releases glucose from a yeast phosphoglycan with alpha-glucosyl phosphate units. The glycosidases also hydrolyze the hexose phosphates of the proper anomeric configuration and structure. The preparations of glycosidases used in this study exhibit specificity for single types of carbohydrate residues and are devoid of phosphatase and phosphodiesterase activities. The glycosidases act on glycosyl-phosphoryl linkages by a stereospecific mechanism and can therefore be used for the determination of the anomeric configuration of glycosyl-phosphoryl units of complex carbohydrates.
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PMID:The determination of the anomeric configuration of glycosyl-phosphoryl linkages of immunogenic phosphoglycans. 240 37

In the newborn lamb, activities of lysosomal enzymes are lower in the duodenum and jejunum than in the ileum. In contrast, there are only minor differences, if any, in activities of lysosomal enzymes between the regions of the small intestine of 5-day-old lambs. In the duodenum, jejunum and ileum, activities of hexosaminidase, alpha-mannosidase, beta-mannosidase, alpha-L-fucosidase and phosphodiesterase are greater in newborn than in 5-day-old lambs. Only in the distal part of the small intestine are activities of beta-glucuronidase, alpha-glucosidase, alpha-galactosidase, beta-galactosidase, acid phosphatase and cathepsin B higher in the newborn than in 5-day-old lambs. Cathepsin B activity is lower in the duodenum and jejunum of the newborn than in 5-day-old lambs.
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PMID:Lysosomal enzymes in the intestine of the newborn lamb. 609 93

Bloodstream forms of Trypanosoma brucei have been screened for the presence of enzymes that could serve as markers for the plasma membrane, flagellar pocket, lysosomes, endoplasmic reticulum and Golgi apparatus in order to study the subcellular organization of the digestive system of the parasite. Acetylesterase, acid DNase, acid phosphatase, acid phosphodiesterase, acid proteinase, acid RNase, alanine aminotransferase, galactosyl transferase, alpha-glucosidase, inosine diphosphatase and alpha-mannosidase were partially characterized and their assays optimized for pH-dependent activity, linearity of reaction with respect to incubation time and enzyme concentration, and the effect of inhibitors and activators. The association of these enzymes with particulate material and the presence of structural latency were investigated. Acid proteinase and alpha-mannosidase are particle-bound and latent in cytoplasmic extracts; they can be activated and solubilized in part by Triton X-100. Similar results were obtained for acid phosphatase, acid phosphodiesterase and inosine diphosphatase. Neutral alpha-glucosidase, though partly sedimentable, does not show latency and is readily solubilized by the detergent. Galactosyl transferase is firmly membrane-bound even in the presence of 0.1% Triton X-100. Cell fractionation by differential centrifugation and density equilibration on sucrose gradients revealed that both alpha-mannosidase and acid proteinase are associated with organelles that band at a density of about 1.20 g/cm3. Inosine diphosphatase, galactosyl transferase, acid phosphatase and acid phosphodiesterase sediment predominantly as microsomal constituents equilibrating at densities between 1.13 and 1.15 g/cm3. In addition, inosine diphosphatase and galactosyl transferase exhibit considerable activity at higher densities (1.18-1.25 g/cm3). Neutral alpha-glucosidase is mainly recovered in the nuclear and microsomal fraction; its particulate part equilibrates as a single band at rho = 1.22 g/cm3. Acetylesterase and acid DNase are largely soluble, whereas acid RNase does not produce distinct sedimentation and banding profiles. In intact cells, neutral alpha-glucosidase and acid phosphatase appear to be highly accessible to their substrates. It is tentatively concluded that (a) acid proteinase and alpha-mannosidase are lysosomal enzymes, (b) acid phosphatase and acid phosphodiesterase are associated with the flagellar pocket and part of the former enzyme probably with the endoplasmic reticulum, (c) galactosyl transferase is a constituent of the Golgi apparatus, and (d) alpha-glucosidase may serve as a marker for the plasma membrane. Inosine diphosphatase may also be derived from the latter structure.
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PMID:Subcellular fractionation of Trypanosoma brucei bloodstream forms with special reference to hydrolases. 624 76

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

The present study examines the role of cardiac lysosomal enzymes in the pathogenesis of the cardiomyopathy that develops in genetically diabetic C57BL/KsJ db+/db+ mice. Db+/db+ mice and littermate controls were sacrificed as age-matched pairs between 5-26 weeks of age. C57BL/6J ob/ob mice and littermates served as other controls. The hearts were excised, homogenized, and the following enzymatic activities measured: N-Acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-glucosaminidase, aryl sulphatase, alpha-mannosidase, alpha-glucosidase, beta-galactosidase, beta glucosidase, total p-nitrophenyl phosphatase, acid phosphatase and 5'-phosphodiesterase type IV. There is a progressive decrease in cardiac lysosomal enzyme activities of db+/db+ mice for the period 5-21 weeks of age. All enzyme activity is depressed significantly during the 9-21 week interval with beta-glucuronidase, aryl sulphatase and beta-glucosidase decreased about 40-50%. The decrease in lysosomal enzyme activity can explain the accumulation of large residual bodies and interstitial material in the myocardium of the db+/db+ animals
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PMID:Lysosomal enzymes in experimental diabetic cardiomyopathy. 678 Feb 37

Homogenates of the posterior latissimus dorsi muscle, a phasic muscle, were fractionated by a one-step zonal centrifugation technique into four major organelle populations and cytoplasmic constituents. These were: (1) Plasma membrane fragments with a modal equilibrium density of 1.10 and containing 5'-nucleotidase, alkaline phosphodiesterase, p-nitrophenylphosphatase and acid phosphatase (beta-glycerophosphate was used as the substrate). (2) Sarcoplasmic reticular fragments which could be further subdivided into calcium transport vesicles, with a model equilibrium density of 1.16, that exhibited calcium uptake; K+-ATPase; leucyl-bet-naphthylamidase; acid phosphodiesterase; acid phosphatase (using cytidine monophosphate as the substrate); and sarcoplasmic reticular lysosomes, with a model equilibrium density of 1.18, possessing dipeptidyl-aminopeptidase II, cathepsin D, alpha-glucosidase, N-acetyl-beta-glucosaminidase, and NADH oxidase activity. (3) Mitochondria with a modal equilibrium density of 1.21. (4) Catalase-containing vesicles with a modal equilibrium density of 1.22; and cytoplasmic constituents (modal density of 1.25) with phosphorylase, pyruvate kinase, myosin-ATPase, aldolase, and protein and RNA content. The purity of these organelles was equal to or better than previous efforts, with a 30-fold purification achieved for 5'-nucleotidase and alkaline phosphodiesterase. These results lend support to the hypothesis that the sarcoplasmic reticulum of phasic muscle, in addition to its specialized role in excitation-contraction coupling, represents a multifunctional membrane system, and that, similar to the smooth endoplasmic reticulum of other cells, it includes some membrane-bound lysosomal enzymes and NADH oxidase.
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PMID:Isopycnic-zonal centrifugation of plasma membrane, sarcoplasmic reticular fragments, lysosomes, and cytoplasmic proteins from phasic skeletal muscle. 721 87

The purpose of the present study was to determine the role of cardiac lysosomal enzymes in the pathogenesis of the cardiomyopathy that develops in the genetically diabetic C57BL/KsJ db+/db+ mice. Db+/db+ mice and littermate controls were sacrificed as age-matched pairs between 5 and 26 weeks of age. C57BL/6J ob/ob mice and littermates served as other controls. Following anesthesia, the hearts were excised, homogenized, and the following enzymatic activities measured: N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-glucosaminidase, aryl sulfatase, alpha-mannosidase, alpha-glucosidase, beta-galactosidase, beta-glucosidase, total rho-nitrophenyl phosphatase, acid phosphatase. and 5'-phosphodiesterase type IV. There is a progressive decrease in cardiac lysosomal enzyme activities of db+/db+ mice for the period 5 to 21 weeks of age. All enzyme activity is depressed significantly during the 9- to 21-week interval: alpha-glucosidase, beta-glucosidase, alpha-mannosidase, beta-galactosidase, acid phosphatase, N-acetyl-beta-galactosaminidase, 5'-phosphodiesterase type IV, and total rho-nitrophenyl phosphatase are reduced approximately 10 to 20 per cent, whereas beta-glucosaminidase, aryl sulfatase, and N-acetyl-beta-glucosaminidase are decreased almost 40 to 50 per cent. In contrast, cardiac lysosomal enzymic activity in the ob/ob mice does not differ significantly from controls aside from aryl sulfatase (20 per cent decrease) and beta-glucosidase (10 per cent decrease). This decrease in lysosomal enzyme activity can explain the accumulation of large residual bodies and interstitial material that occurs in the myocardium of the db+/db+ animals as part of the cardiomyopathy.
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PMID:Lysosomal enzymes in the heart of the genetically diabetic mouse. 742 Nov 26

The pseudotetrasaccharide acarbose, previously known as a potent inhibitor of intestinal alpha-glucoside hydrolases, was investigated with regard to its influence on islet lysosomal enzyme activities and the insulin secretory processes. We observed that acarbose was a potent inhibitor of mouse islet lysosomal acid glucan-1,4-alpha-glucosidase activity, EC50 approximately 5 mumol/l, as well as of acid alpha-glucosidase activity. In contrast, acarbose did not influence other lysosomal enzyme activities such as acid phosphatase and N-acetyl-beta-D-glucosaminidase. Neutral alpha-glucosidase (endoplasmic reticulum) was only moderately inhibited in homogenate and was unaffected in intact islets. Incubation of isolated mouse islets with acarbose revealed that the pseudotetrasaccharide was a strong inhibitor of glucose-induced insulin secretion, EC50 approximately 500 nmol/l, and a significant inhibition was already observed at a concentration of acarbose as low as 100 nmol/l. The acarbose analogue maltotetrose did not influence either glucose-induced insulin release or islet lysosomal enzyme activities. Further, acarbose as well as two other alpha-glucoside hydrolase inhibitors, the deoxynojirimycin derivatives miglitol and emiglitate, did not affect islet glucose oxidation at low or high glucose levels. Acarbose also inhibited insulin release induced by the sulfonylurea glibenclamide, whereas insulin secretion stimulated by the cholinergic muscarinic agonist carbachol or the phosphodiesterase inhibitor isobutylmethylxanthine was unaffected by the drug. Moreover, complementary in vivo experiments showed that pretreatment of mice with acarbose to allow for endocytosis of the compound markedly suppressed the insulin secretory response to an intravenous glucose load.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The pseudotetrasaccharide acarbose inhibits pancreatic islet glucan-1,4-alpha-glucosidase activity in parallel with a suppressive action on glucose-induced insulin release. 778 51


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