Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The levels of fructose, acid phosphatase, citric acid, zinc, maltase, testosterone, prostaglandin E, putrescine, spermidine and spermine were compared in ejaculates collected by masturbation and after coitus in the same individuals. Coitus was associated with a significantly larger semen volume and increased concentrations and total amounts of prostaglandin E and polyamines in the ejaculate. In contrast, the concentrations of the conventional glandular parameters remained relatively unaffected, although a slight dilution of the seminal vesicle contribution to the ejaculate occurred after coitus. In the majority of cases, ejaculates provided by masturbation were significantly enriched in spermatozoa, but the total contributions under both conditions remained the same. It is concluded that the assessment of semen quality in male individuals using the conventional parameters of accessory gland function can be made with ejaculates provided by masturbation or coitus.
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PMID:Ejaculate composition after masturbation and coitus in the human male. 355 35

Nineteen hydrolytic enzymes were detected in individual adult Pergamasus longicornis (Berlese) mites--amylase, hide protease, alkali phosphatase, esterase (C4), esterase lipase (C8), lipase (C14), leucine arylamidase, valine arylamidase, cystine arylamidase, acid phosphatase, phosphoamidase, alpha-galactosidase, beta-galactosidase, beta-glucuronidase, alpha-glucosidase, beta-glucosidase, N-acetyl-beta-glucosaminidase, alpha-mannosidase, and alpha-fucosidase. All but the phosphatases were detected for the first time. Tryptic and chymotryptic activity were consistently not demonstrable. Comparisons are made with saprophagous mites. No clear enzymic specialization for predation was found.
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PMID:Digestion in the soil predatory mite Pergamasus longicornis (Berlese) (Acari: Mesostigmata: Parasitidae)--detectable hydrolases. 356 25

The distribution of a series of marker enzymes in the gastric mucosa was studied by analysis of homogenized biopsy specimens from the lesser and greater curvature of the body and antrum, respectively, obtained from 11 control patients. The activities varied significantly between the regions for the membrane enzymes lactase (p less than 0.0001), neutral-alpha-glucosidase (p less than 0.005), alkaline phosphatase (p less than 0.01), leucyl-beta-naphthylamidase (p less than 0.005), and 5'-nucleotidase (p less than 0.0001) and the lysosomal enzymes N-acetyl-beta-D-glucosaminidase (p less than 0.0001) and acid beta-glucuronidase (p less than 0.0001), using analysis of variance modified for repeated measurements. When paired comparisons between regions were evaluated, the enzyme activities of the antral regions were significantly higher than those of the body stomach. The activities of gamma-glutamyltransferase, acid phosphatase, and the mitochondrial enzyme monoamine oxidase did not alter between regions, nor did the protein to DNA ratio. The demonstrated biochemical distinction between antrum and body of the stomach may be explained by different physiological and histological properties of the two parts.
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PMID:Enzyme activities in biopsy specimens from human gastric mucosa. 381 4

Previous studies have shown that chronic administration of D-galactosamine (GalNH2) in rats produces alpha 1-antiprotease (AAP) deficiency and causes accumulation of aberrantly glycosylated AAP in hepatic granules. In order to examine the disordered mechanism which produces this altered glycosylation, the activities of 6 glycosidases in liver homogenates of control and AAP-deficient rats were determined. GalNH2 treatment increases acid pH glycosidase activity, while it decreases intermediate pH alpha-mannosidase and alpha-glucosidase activities. beta-D-Glucosidase, beta-D-mannosidase and beta-D-N-acetylglucosaminidase activities, measured at acid pH, increase more than 2-fold in the GalNH2-treated rats compared to controls. alpha-D-Glucosidase activity measured at intermediate pH decreases 2.5-fold in the experimental rats. alpha-L-Fucosidase and acid phosphatase activities are not significantly changed by GalNH2 treatment. alpha-D-Mannosidase activity can be separated into 2 fractions by ion exchange chromatography. Acid pH alpha-D-mannosidase is increased nearly 2-fold in the GalNH2-treated rats. Intermediate pH alpha-D-mannosidase optimum is decreased alpha-D-mannosidase activities have been observed in humans with AAP deficiency. alpha-Glucosidases and alpha-mannosidases play a crucial role in glycoprotein synthesis. The altered synthesis and structure of AAP in GalNH2-induced AAP deficiency may be a reflection of altered enzyme activities.
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PMID:Altered glycosidase activity in the liver of rats with galactosamine-induced alpha 1-antiprotease deficiency. 383 42

The exoglycosidases beta-N-acetyl-D-glucosaminidase, beta-N-acetyl-D-galactosaminidase, alpha-1-fucosidase, alpha-D-glucosidase and alpha-D-mannosidase, and a non-specific acid phosphohydrolase are present at high levels in extracts of adult and muscle-stage (L1) Trichinella spiralis and at lower (5-30-fold) levels in extracts of the newborn larvae. The enzyme activities from the L1 extract were characterized. All displayed maximum activity at acid pH. beta-N-acetyl-D-glucosaminidase and beta-N-acetyl-D-galactosaminidase had identical molecular weights (110 000), pH optima (5.0), and isoelectric points (5.7) indicating that both of these substrate specificities reside in the same protein molecule. alpha-1-Fucosidase had a molecular weight of 125 000 and exhibited two pH optima (5.0 and 6.0) and four isoelectric points (5.9, 6.4, 6.7 and 7.1) indicating its presence in multiple molecular forms. alpha-D-Glucosidase had a molecular weight of 85 000, a pH optimum of 6.0 and an isoelectric point of 5.2; alpha-D-mannosidase had a molecular weight of 192 000, a pH optimum of 6.0 and an isoelectric point of 4.5; and acid phosphatase had a molecular weight of 81 000, a pH optimum of 6.0 and two isoelectric points (4.8 and 5.9) indicating its existence in two molecular forms. The same glycosidases and acid phosphatase were detected also in culture fluids collected after 15-20-h incubation of both L1 and adults. As in the worm extracts, beta-N-acetyl-D-glucosaminidase was present in these culture fluids at the highest activity with acid phosphatase present at the next highest activity.
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PMID:Glycosidases of Trichinella spiralis. 389 59

Several approaches were adopted for the disruption and removal of the tegumental surface from protoscoleces of the horse strain of the hydatid organism, Echinococcus granulosus. The effectiveness of each method and the purity of subsequent microthrix-enriched fractions obtained by differential centrifugation were evaluated by electron microscopy, by the amount of protein released and by the degree of enrichment of surface plasma membrane marker enzymes. Incubation in saponin for 10 min produced the purest microtriche preparation, but in low yield; freeze/thawing, incubation in Triton X-100 for 10 min or in saponin for 20 min produced fractions containing significant amounts of relatively pure microtriches, but mild homogenization was a poor method for surface disruption and subsequent isolation of microtriches. Phosphodiesterase, adenosine triphosphatase (total and ouabain-inhibited), leucine aminopeptidase and glutamyltransferase were active in the protoscoleces but none were enriched in any of the microthrix fractions. In contrast, alkaline phosphatase, acid phosphatase, 5' nucleotidase and maltase were enriched significantly in all of the isolated microtriche preparations, which suggests that these enzymes are predominantly surface membrane bound. The protein profiles of the microthrix-enriched fractions, following SDS-PAGE, were basically similar, although there were some qualitative and quantitative differences in the proteins released by each isolation procedure. Three major PAS-staining components were present in all the preparations and these probably originated from the glycocalyx. One of these PAS-positive components, with an approximate molecular weight of 110 kDa, may be a glycoprotein specific to the horse strain of E. granulosus.
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PMID:Isolation, fractionation and partial characterization of the tegumental surface from protoscoleces of the hydatid organism, Echinococcus granulosus. 398 50

The ingestion of (14)C-labeled 9,10-dimethyl-1,2-benzanthracene particles, the extracellular release of acid phosphatase, ribonuclease, and alpha-glucosidase, and the egestion of preingested dimethylbenzanthracene particles by Tetrahymena taken from logarithmically growing cultures and resuspended in a dilute salt solution were followed in the presence of several pharmacologic agents. Serotonin, caffeine, and, to a lesser extent, dibutyryl cyclic AMP increased the rate of particle ingestion, but did not alter the rate of release of the three acid hydrolases studied. Added catecholamines did not affect either particle ingestion or acid hydrolase release, but particle ingestion was inhibited by the catecholamine antagonists, dichloroisoproterenol, desmethylimipramine, reserpine, and phenoxybenzamine. These drugs also increased the release of acid phosphatase and ribonuclease in 5-h incubations. Desmethylimipramine acted within 1 h to increase acid hydrolase release, but the effect of dichloroisoproterenol developed more slowly and was secondary to a change in cellular content of the hydrolases. Desmethylimipramine increased the energy of activation for the release of acid phosphatase, while dichloroisoproterenol did not. Both of these drugs enhanced the egestion of preingested dimethylbenzanthracene particles, supporting the view that acid hydrolase release occurs through a cytoproct egestion mechanism. Particle ingestion was also inhibited by colchicine, vinblastine, and cytochalasin B, but these agents had no effect on acid hydrolase release, thus further differentiating the properties of the ingestion mechanism from those of the egestion mechanism. It appears that both microtubules and microfilaments play a role in the ingestion process and that this process may be controlled in part by a cyclic AMP-mediated serotoninergic and adrenergic system.
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PMID:Lysosomal physiology in Tetrahymena. 3. Pharmacological studies on acid hydrolase release and the ingestion and egestion of dimethylbenzanthracene particles. 415 46

Some intestinal enZymes were assayed which were related to: (i) Cellular proliferation, for example, aspartate carbamoyltransferase, thymidine kinase, uridine kinase, and dihydroorotase; (ii) cellular differentiation, for example, lactase, invertase, maltase, alkaline phosphatase, and dipeptidase; and (iii) lysosomes, for example, beta-glucuronidase, acid beta-galactosidase, and acid phosphatase. These enzymatic determinations can be used to distinguish the crypt from the villus during healthy or diseased states.
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PMID:Intestinal enzymes: indicators of proliferation and differentiation in the jejunum. 431 2

Log-phase Tetrahymena were washed and resuspended in a dilute salt solution supplemented with glucose, acetate, pyruvate, or carmine, as desired, and then incubated for 5 h. Intra- and extracellular activities of acid phosphatase, alpha-glucosidase, and ribonuclease were assayed. Extracellular activities were corrected for proteolytic degradation. The three nutritive substrates affected both the amount and pattern of extracellular enzyme release, but carmine had no effect. Intracellular activities declined early in the starvation period, but partially recovered with time, particularly alpha-glucosidase activity. Acetate reduced the decline in acid phosphatase activity; acetate and glucose enhanced the recovery of alpha-glucosidase activity; carmine had no effect on intracellular enzyme activities. Protein content changed little and was unaffected by the addition of substrates. Glycogen content increased during incubation; acetate and glucose enhanced the increase.
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PMID:Lysosomal physiology in Tetrahymena. I. Effect of glucose, acetate, pyruvate, and carmine on intracellular content and extracellular release of three acid hydrolases. 463 42

The synthesis of the glycoprotein enzymes, invertase and acid phosphatase, by protoplasts of Saccharomyces mutant 1016, is inhibited by 2-deoxy-d-glucose (2-dG) after a 20- to 30-min lag period under conditions (external sugar to 2-dG ratio of 40:1) which cause only a slight decrease in total protein synthesis. Formation of one intracellular enzyme, alpha-glucosidase, is also sensitive, but production of another, alkaline phosphatase, is unaffected. A nonmetabolized glucose analogue, 6-deoxy-d-glucose, had no inhibitory effect. The total uptake of external fructose and maltose was decreased by 2-dG after a lag period of about the same duration as that before the inhibition of synthesis of enzymes or of mannan and glucan; during this time 2-dG was taken up by the protoplasts and accumulated primarily as 2-dG-6-phosphate (2-dG-6-P). Studies in vitro showed that 2-dG-6-P inhibits both yeast phosphoglucose isomerase and phosphomannose isomerase. The intracellular levels of the 6-phosphates of glucose, fructose, and mannose did not increase in the presence of 2-dG. We suggest that the high internal level of 2-dG-6-P blocks synthesis of the cell wall polysaccharides and glycoproteins in two ways. It directly inhibits the conversion of fructose-6-P to glucose-6-P and to mannose-6-P. At the same time, it restricts the transport of fructose and maltose into the cell; however, the continuing limited uptake of the sugars still provides sufficient energy for protein synthesis. The cessation of alpha-glucosidase synthesis is probably a result of depletion of the internal pool of maltose (the inducer). Our findings support the suggestion that restriction of synthesis of the carbohydrate moiety of glycoproteins reduces formation of the active enzyme.
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PMID:Inhibition by 2-deoxy-D-glucose of synthesis of glycoprotein enzymes by protoplasts of Saccharomyces: relation to inhibition of sugar uptake and metabolism. 505 66


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