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
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.
...
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
Twelve acid hydrolases, 4 near-neutral hydrolases, and alkaline phosphatase were demonstrated in 0.34 M sucrose homogenates of Trypanosoma cruzi strain Y: p-nitrophenylphosphatase and alpha-naphthylphosphatase, with optimum pH at approximately 6.0; alpha=ga;actpsodase. beta=ga;actpsodase. beta=g;icpsodase,
N-acetyl-beta-glucosaminidase
, cathepsin A and peptidase I and III, with optimum pH between 5.0 and 6.0; and arylsulfatase, cathepsin D, alpha-arabinase and alpha-mannosidase with optimum pH at approximately 4.0. alpha-Glucosidase, glucose-6-phosphatase and peptidase II had optimum pH at approximately 7.0. beta-Glycerophosphatase had a broad pH-activity curve from 4,0 to 7.4, with maximum activity at pH 7.0. The main kinetic characteristics of these enzymes and their quantitative assay methods were studied. No activity was detected for alpha-fucosidase, beta-xylosidase, beta-glucuronidase, elaidate esterase, acid lipase, and
alkaline phosphodiesterase
.
...
PMID:Acid and neutral hydrolases in Trypanosoma cruzi. Characterization and assay. 4 19
1. A mixed membrane fraction prepared from pig platelets was subfractionated, using the "B 14" zonal rotor, into two distinct subpopulations of membrane vesicles, each associated with a different
phosphodiesterase
activity. 2. The lighter subfraction (MI) was enriched 7-8 fold with bis-(p-nitrophenyl) phosphate
phosphodiesterase
activity and the denser subfraction (MII) showed a similar degree of enrichment of 5'dTMP-p-nitrophenyl ester
phosphodiesterase
activity. 3. Assays for other enzyme activities revealed slight enrichement (approx. 2 fold) of acid phosphatase, 3'-dTMP-p-nitrophenyl ester
phosphodiesterase
and beta-glucuronidase activities in MI, and beta-galactosidase in MII. Cyclic AMP phosphodiesterase, lactate dehydrogenase and
N-acetyl-beta-glucosaminidase
showed negligible activity in both MI and MII, and succinate dehydrogenase activity could not be detected in either subfraction. 4. Chemical analyses of the membrane subfractions demonstrated that MI contained approx. twice as much cholesterol, phospholipid, sialic acid and hexosamine per unit weight of protein than MII. These results are consistent with our previously reported observations from surface-labelling experiments, which indicated that MI was derived principally from the platelet surface-exposed membranes and that MII was probably intracellular in origin. 5. Analysis of the membrane polypeptides by sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed the presence of 12-15 components, in each subfraction, in the mol. wt. range 12000-200000, including a prominent band of approx. mol. wt. 46000, which has beeen identified to be actin. Qualitative as well as possible quantitative differences were apparent in that MII contained three components in addition to those present in MI. 6. Analysis of the periodate-Schiff staining components by sodium dodecyl sulphate-polyacrylamide gel electrophoresis demonstrated the presence of 4 major glycoproteins in both subfractions with apparent mol. wt. ranging from approx. 95000 to 150000; in addition two minor components were also present. Further, a very fast-migrating band, which did not stain with Coomassie blue, was observed in both MI and MII and probably represents lipid material.
...
PMID:Enzymatic and chemical analyses of pig platelet membrane subfractions isolated by zonal centrifugation. 127 16
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.
...
PMID:The determination of the anomeric configuration of glycosyl-phosphoryl linkages of immunogenic phosphoglycans. 240 37
Perfluoro-n-decanoic acid (PFDA) produces toxic effects in rodents similar to those caused by 2,3,7,8-tetrachloro-dibenzo-p-dioxin. A single, intraperitoneal dose (50 mg/kg) of PFDA to Sprague-Dawley rats caused disruption of the endoplasmic reticulum, mitochondrial swelling and increases in intracellular lipid droplets in hepatocytes similar to effects reported previously in dioxin toxicity. PFDA treatment led to large decreases in the activity of plasma membrane
alkaline phosphodiesterase
and mitochondrial cytochrome c oxidase without affecting lysosomal
N-acetyl-beta-glucosaminidase
, endoplasmic reticulum NADPH-cytochrome c reductase or peroxisomal catalase activities. PFDA treatment led to moderate peroxisome proliferation and to very large (20-40-fold) increases in the activity of fatty acyl-CoA oxidase, the rate-limiting enzyme in the peroxisomal system of fatty acid beta-oxidation.
...
PMID:Perfluoro-n-decanoic acid: induction of peroxisomal beta-oxidation by a fatty acid with dioxin-like toxicity. 336 97
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.
...
PMID:Isopycnic-zonal centrifugation of plasma membrane, sarcoplasmic reticular fragments, lysosomes, and cytoplasmic proteins from phasic skeletal muscle. 721 87
Proximal tubules were isolated in highly pure form from rabbit cortices by a mechanical procedure that is known to preserve the structural and metabolic aspects of the tubular cells. Postnuclear supernates prepared from the isolated tubules were subjects to isopycnic centrifugation in linear sucrose gradients. The enzyme activities associated with the plasma membrane (gamma-glutamyl transpeptidase, amino-peptidase M, alkaline phosphatase, Na-K-ATPase, and
phosphodiesterase I
) exhibited sharp unimodal frequency-density profiles with a median density near 1.16 g/ml, which shifted to a heavier density when treated with digitonin. The lysosomal enzymes,
N-acetyl-beta-glucosaminidase
, alpha-mannosidase, and cathepsin B, and the peroxisomal enzyme catalase exhibited particle-associated activity near a density of 1.22 g/ml. Disruption of these particles by freezing and thawing resulted in these activities appearing in the rho = 1.10 g/ml region of the gradient where the soluble cytosolic enzyme, phosphoglucomutase, exhibited activity. Cytochrome oxidase activity typical of mitochondria gave a sharp unimodal profile at rho = 1.18 g/ml. Microsomal glucose-6-phosphatase and NADPH: cytochrome c reductase activities gave median densities near 1.16 g/ml, which did not change after incubation with digitonin. Galactosyl transferase activity gave a skewed profile at rho = 1.16 g/ml and showed a slight shift to heavier density after digitonin. This study of the enzymatic activities and density gradient distribution of the components of the proximal tubule cells provides the methodology for the further study of the cellular processing of endogenous and exogenous substances by this vital cell type.
...
PMID:Analytical cell fractionation of isolated rabbit renal proximal tubules. 730 Jan 16
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.
...
PMID:Lysosomal enzymes in the heart of the genetically diabetic mouse. 742 Nov 26
Lysosomal accumulation of unesterified (free) cholesterol, following the phagocytic incorporation of cholesteryl oleate lipid droplets, was quantitatively characterized in a murine J774 macrophage foam cell model. The induction of phagocytic incorporation by the macrophages, using an inverted culture technique, allowed the rapid delivery of large amounts of cholesteryl ester droplets to the lysosomes, leading to the subsequent generation of free cholesterol. The lysosomally generated free cholesterol was differentiated from the membrane cholesterol by a double radiolabeling procedure. Free cholesterol accumulation was quantitated in a population of low density lipid-filled lysosomes prepared by ultracentrifugal isolation of a floating lipid fraction from a homogenate of the cholesteryl ester-loaded cells. About 10% of the total
N-acetyl-beta-glucosaminidase
activity, a lysosomal marker, was recovered in the lipid fraction. Negligible amounts of
alkaline phosphodiesterase
-1, a plasma membrane marker, or membrane cholesterol were present in this fraction. Electron microscopic and cytochemical analysis of the isolated lipid fraction revealed the presence of lysosomes in the fraction with a diameter ranging from 1.5 to 4 microns. Continued hydrolysis of incorporated cholesteryl ester over a 24-h incubation resulted in approximately 30% of the generated free cholesterol in lipid-filled lysosomes. The accumulation of free cholesterol occurred whether or not the cholesterol esterifying enzyme, acyl-CoA: cholesterol acyltransferase, was inhibited. In addition, substantial amounts of free cholesterol accumulated even in the presence of efficient cholesterol acceptor particles, apolipoprotein high density lipoprotein-phosphatidylcholine complexes which stimulate cholesterol efflux. Also, increased accumulation of free cholesterol in the lipid fraction was observed when cholesteryl ester-loaded cells were treated with the compound U-18666A which blocks the movement of lysosomal cholesterol. The data demonstrate that the phagocytic incorporation and hydrolysis of cholesteryl ester lipid droplets by macrophage foam cells lead to a substantial accumulation of free cholesterol in the lipid-filled lysosomes. This process could result in a build-up of lysosomal free cholesterol in macrophage foam cells during the progression of atherosclerotic plaque.
...
PMID:Lysosomal accumulation of unesterified cholesterol in model macrophage foam cells. 848 53
We present evidence that protein bodies constitute the principal lytic compartment in storage parenchyma cells of mung bean cotyledons and propose that they play a role in cellular autophagy. We developed a method to isolate protein bodies by incubating tissue slices with cell wall-degrading enzymes and fractionating the cellular organelles on a Ficoll gradient. About 75-80% of the protein bodies present in the protoplasts were recovered intact in a band at the 5/25% Ficoll interface. This band contained a similar proportion of the cellular alpha-mannosidase,
N-acetyl-beta-glucosaminidase
, ribonuclease, acid phosphatase,
phosphodiesterase
, and phospholipase D. beta-Amylase was present in the cells but not in the protein bodies. Ultrastructural observations showed that on the 3rd day of seedling growth protein bodies contain small vesicles (0.3-1.0 mum) with a cytoplasmic content (ribosomes, membrane vesicles, mitochondria). Later in seedling growth these vesicles appeared empty. We believe that these are autophagic vesicles resulting from invaginations of the protein body membrane and that their cytoplasmic contents are digested by the acid hydrolases present in the protein bodies.
...
PMID:Protein bodies of mung bean cotyledons as autophagic organelles. 1659 58
1