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

1. alpha-D-mannosidase, beta-D-galactosidase, alpha-L-fucosidase, beta-N-acetylgalactosaminidase, alpha-D-glucosidase and acid phosphatase activities were studied in circulating blood leukocytes from Sus scropha var. domestica L. (pig) and Equus asinus x caballus (mule) by spectrophotometric procedures using p-nitrophenyl derivatives as substrates and three different buffer solutions. 2. The highest specific activity corresponds to acid phosphatase. The specific activities of the glycosidases, all relatively close together in all cases, were low in comparison with that of phosphatase. 3. Generally, each of the above-mentioned enzymes shows one common peak for the pH optimum between 3.5 and 6.0, except alpha-D-glucosidase, which shows two peaks. 4. The pH optima values are generally similar in three buffer solutions employed. 5. Specific activities of the studied enzymes show a parallelism in leukocytes from both pig and mule. Also, this parallelism is observed in their pH optima values. 6. Thermal stability of alpha-D-mannosidase is high whereas that of acid phosphatase is low, in both materials. For other enzymes, differences in the thermal stability was observed according to their source.
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PMID:Comparative study on the activity, pH optimum and thermal stability of some glycosidases and acid phosphatase from pig and mule leukocytes. 4 40

Rats bearing Reuber H-35 or Novikoff hepatomas and mice bearing L1210 or L5178Y murine leukemias exhibited elevated serum levels of fetuin : N-acetylneuraminic acid transferase (EC 2.4.99.1) activity. The serum transferase activity could be correlated with the growth rate of the tumor; in animals bearing the more rapidly growing Novikoff hepatoma, activity was higher than in animals bearing the Reuber H-35 hepatoma. Higher transferase levels were also found in L1210 leukemic mice than in mice with the slightly slower growing L5178Y leukemia. Serum from rats bearing Reuber H-35 hepatoma and mice bearing L1210 murine leukemia had elevated levels of alpha- and beta-glucosidase (EC 3.2.1.20 and EC 3.2.1.21), alpha- and beta-galactosidase (EC 3.2.1.22 and (3.2.1.23), beta mannosidase (EC 3.2.1.25), alpha- and beta-fucosidase (EC 3.2.1.- and EC 3.2.1.38), beta-N-acetylglucosaminidase (EC 3.2.1.30) and acid phosphatase (EC 3.1.3.2); alpha-mannosidase (EC 3.2.1.24), beta-N-acetylgalactosaminidase (EC 3.2.2.-) and beta-xylosidase (EC 3.2.1.37) were not elevated. In animals bearing Reuber H-35 hepatoma, host liver levels of glycosidases, beta-glucuronidase (EC 3.2.1.31) and acid phosphatase were elevated over both the control and the hepatoma values. The data are interpreted to mean that the tumors or various host tissues release large quantities of enzymes into the serum and that enzyme levels in host organs may also be affected by the tumor.
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PMID:Serum and host liver activities of glycosidases and sialyltransferases in animals bearing transplantable tumors. 17 98

The activity of five glycohydrolases was measured in the plasma of Chinese hamsters from eight highly inbred lines in the Upjohn colony. The diabetic animals showed elevated activities of plasma beta-D-galactosidase, N-acetyl-beta-D-glucosaminidase and N-acetyl-beta-D-galactosaminidase but similar activities of plasma alpha-D-glucosidase and alpha-D-galactosidase to the nondiabetic animals. Line-specific variation was observed in all five enzymes and anomalies were especially evident in N-acetyl-beta-D-glucosaminidase and N-acetyl-beta-D-galactosaminidase activity. In two diabetic lines, AC and Z, activities of these two enzymes were not elevated although significant correlation was found with blood sugar levels. The pronounced difference in the plasma activity of N-acetyl-beta-D-glucosaminidase in two diabetic lines, XA and AC, did not involve plasma inhibitors or activators, as evidenced by the coincidence in observed and calculated activities in mixed plasma samples, or specific isozymes, concluded from the similar elution profiles on ion-exchange column and thermostability curves. These data suggest that diabetes-related changes in plasma glycohydrolase activities are dictated by genetic factors and may be involved in the development of complications.
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PMID:Acid glycohydrolase in Chinese hamster with spontaneous diabetes. IV. Diabetes- and line-dependent variation in plasma enzyme activity. 21 99

The pH optima and apparent Km and Vmax values were determined for nine glycosidases of the retinal pigment epithelium (RPE) of the calf. In terms of micromoles of substrate cleaved per milligram protein per hour, the following relative order of enzymatic activities was observed: beta-N-acetylglucosaminidase greater than alpha-glucosidase = beta-N-acetylgalactosaminidase greater than alpha-mannosidase greater than beta-galactosidase greater than beta-glucosidase greater than alpha-fucosidase greater than alpha-galactosidase greater than beta-glucuronidase. The pH optimum of each of these enzymes was in the acidic range (below pH 6). All these findings refer to enzymatic activities of bovine RPE preparations obtained by the brushing procedure of Glocklin and Potts and washing as described by Berman and Feeney. Thus they may relate to those activities associated with particulate components of the RPE cell and not to the more soluble glycosidases. The distribution of the glycosidases between the washes of the cells and the final pellet of bovine RPE cells was examined. The activities of 10 glycosidases in the RPE of the embryonic chick were also examined. Neither beta-mannosidase nor beta-fucosidase activities could be detected in washed bovine RPE cells, although beta-mannosidase was detected in RPE of the embryonic chick. The presence of isoenzymes of beta-glucuronidase in bovine RPE was indicated. Specificity by beta-glucuronidase of bovine RPE for synthetic substrates was observed.
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PMID:Glycosidases of the retinal pigment epithelium. 70 Sep 67

KB cells were synchronized by a double thymidine block procedure. An investigation was made of the activities of alpha-L-fucosidase (EC 3.2.1.51), alpha-D-galactosidase (EC 3.2.1.22), beta-D-galactosidase (ec 3.2.1.23), alpha-D-glucosidase (EC 3.2.1.20), beta-D-glucosidase (EC 3.2.1.21), alpha-D-mannosidase (EC 3.2.1.24), beta-D-N-acetylgalactosaminidase (EC 3.2.1.53), and beta-D-N-acetylglucosaminidase (EC 3.2.1.52) from synchronized cultures, using appropriate artificial substrates. Ceramide glucosidase (EC 3.2.1.45) and ceramide trihexosidase levels (EC 3.2.1.47) were also investigated at various stages in the cell cycle, using appropriate glycosphingolipid substrates. Whereas each of these enzymes exhibited some activity throughout the cell cycle, peak activity (2- to 6-fold increase) occurred late in the S phase. Two molecular forms of ceramide glucosidase (optimal activity at pH 4.0 and pH 6.0) and two forms of ceramide trihexosidase (pH 4.0 and pH 7.5) were identified. Peak levels of the forms that preferred the relatively acid pH occurred earlier in the S phase of the cell cycle than those of the forms that were more active at the higher pH. The possibility that the forms with optimal activity at pH 4 are precursors of those with optimal activity at pH 6 to 7.5 is discussed. Precipitation of beta-galactosidase of synchronized KB cells with specific antibody revealed that changes in the activity of this enzyme during the cell cycle were the result of fluctuations in the amount of the enzyme.
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PMID:Glycosphingolipid glycosyl hydrolases and glycosidases of synchronized human KB cells. 115 Jun 49

A biochemical scheme was developed by which strains of Streptococcus constellatus, Streptococcus intermedius, and Streptococcus anginosus can reliably be distinguished from within the "Streptococcus milleri group." Strains identified as S. intermedius were differentiated by the ability to produce detectable levels of alpha-glucosidase, beta-galactosidase, beta-D-fucosidase, beta-N-acetylgalactosaminidase, beta-N-acetylglucosaminidase, and sialidase with 4-methylumbelliferyl-linked fluorogenic substrates in microdilution trays after 3 h of incubation at 37 degrees C, together with the production of hyaluronidase. Strains of S. constellatus and S. anginosus were differentiated by the production of alpha-glucosidase and hyaluronidase by the former and the production of beta-glucosidase by the latter. The majority of strains of the S. milleri group obtained from dental plaque were identified as S. intermedius, as were most strains isolated from abscesses of the brain and liver. Strains of S. constellatus and S. anginosus were from a wider variety of infections, both oral and nonoral, than were strains of S. intermedius, with the majority of strains from urogenital infections being identified as S. anginosus.
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PMID:Phenotypic differentiation of Streptococcus intermedius, Streptococcus constellatus, and Streptococcus anginosus strains within the "Streptococcus milleri group". 238 Mar 75

Electron inactivation analysis with 16 MeV electrons was used to determine the functional target size of a number of commonly studied lysosomal hydrolases. Observed values ranged from a low of 62 000 +/- 4000 Da for beta-galactosidase to a high of 200 000 +/- 17 500 Da (mouse beta-glucuronidase). One group of lysosomal hydrolases (N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, alpha-galactosidase, beta-mannosidase, beta-glucosidase, arylsulphatase A and sphingomyelinase) had target sizes in the range 100 000-120 000 Da, whereas alpha-glucosidase and alpha-fucosidase exist as complex multimers in the 150 000-160 000 Da range. Analysis of freeze-dried cell material showed little evidence of species (mouse versus human) variation in the functional size of most lysosomal hydrolases with the exception of beta-glucuronidase. Our findings suggest the potential usefulness of lysosomal hydrolases as endogenous marker enzymes in studies where the target size of proteins of unknown molecular mass is to be determined.
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PMID:Functional lysosomal hydrolase size as determined by radiation inactivation analysis. 315 87

In Creutzfeldt-Jakob disease (CJD), there are prominent ultrastructural alterations of the plasma membrane, which contains many glycolipids and glycoproteins. Glycosidases can degrade glycolipids and glycoproteins. Gangliosides, a subset of glycolipids, are decreased in amount at the terminal stages of CJD, and CJD infectivity is closely associated with membrane rich fractions. We therefore studied 10 glycosidases, and found a statistically significant increase in beta-xylosidase, beta-glucuronidase, N-acetyl-beta-D-glucosaminidase and N-acetyl-beta-D-galactosaminidase activities in CJD. In contrast, alpha-glucosidase, beta-glucosidase, alpha-galactosidase, alpha-mannosidase, alpha-fucosidase, and beta-galactosidase were not significantly changed. The above results are consistent with degenerative membrane changes observed morphologically, and with increased degradation of sugar residues on lipids and/or proteins. These changes may be effected by the accumulation of the CJD agent in cell membranes. We suggest that the higher activities of these enzymes in CJD may be partially responsible for some of the structural and biochemical alterations in CJD infected brains.
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PMID:Cerebral glycosidases in experimental Creutzfeldt-Jakob disease. 328 70

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

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


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