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)

Sucrase-isomaltase deficiency is an inherited disaccharidase deficiency that leads to malabsorption of sucrose, with resulting diarrhea and abdominal distention and cramps. We investigated the sucrose-splitting effect of viable yeast cells in eight children with congenital sucrase-isomaltase deficiency, by means of the sucrose hydrogen breath test. This test is based on the fact that hydrogen is released from the malabsorbed sucrose by the colonic microflora. We found that 0.3 g of lyophilized Saccharomyces cerevisiae, given after loading with 2 g of sucrose per kilogram of body weight, reduced hydrogen excretion in all patients, on average by 70 percent, in parallel with a complete loss or evident reduction of clinical symptoms. In vitro, lyophilized and fresh S. cerevisiae (fresh baker's yeast) had appreciable sucrase activity, a low isomaltase and maltase activity, and virtually no lactase activity. The sucrase activity was more inhibited by undiluted than by diluted gastric juice. We conclude that patients with congenital sucrase-isomaltase deficiency who intentionally or unintentionally consume sucrose can ameliorate the malabsorption by subsequently ingesting a small amount of viable yeast cells, preferably on a full stomach.
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PMID:Enzyme-substitution therapy with the yeast Saccharomyces cerevisiae in congenital sucrase-isomaltase deficiency. 355 46

Three alpha-glucosidases which passed under the names of transglucosidase (from Aspergillus niger), maltase (from Brewers yeast), and isomaltase (from Bakers yeast) for reasons of their substrate specificities and transfer actions, were purified to electrophoretically pure states. These purified alpha-glucosidases were made uniform in the hydrolyzing activities using p-nitrophenyl alpha-glucopyranoside (alpha-p-NPG) and were reacted with p-nitrophenyl alpha-xylopyranoside (alpha-p-NPX) or isoprimeverose (xylopyranosyl-alpha-1,6-glucopyranose), which are typical substrates of alpha-xylosidase. Only Asp. niger alpha-glucosidase among them hydrolyzed alpha-p-NPX and isoprimeverose. Further the substrate specificities of three alpha-glucosidases and two alpha-xylosidases (I and II from Asp. flavus MO-5) were investigated on maltose, isomaltose, alpha-p-NPG, isoprimeverose, and alpha-p-NPX in detail, and kinetic parameters [Km, Vmax, and molecular activity (Ko)] were estimated and compared with each other. In the comparison of kinetic parameters, Asp. niger alpha-glucosidase showed a broad specificity, that is, containing isoprimeverose in addition to maltose, isomaltose, and alpha-p-NPG. Though this enzyme barely hydrolyzed alpha-p-NPX too, the velocity was very slow. Though both yeast alpha-glucosidases barely hydrolyzed alpha-p-NPX or isoprimeverose too, these substrates were not good for yeast enzymes. On the other hand, two alpha-xylosidases showed narrow specificities, such that the substrates except for alpha-p-NPX and isoprimeverose were not hydrolyzed at all. The action on isoprimerose by Asp. niger alpha-glucosidase was completely the same as that on isomaltose at optimum pH, optimum temperature, inhibition pattern of hydrolyzing activity by 1-deoxynojirimycin, and transfer action pattern. Accordingly, we interpret these results as indicating that the hydrolyzations of isomaltose and isoprimeverose by Asp. niger alpha-glucosidase were catalyzed at the same active site. Asp. niger enzyme that has both alpha-glucosidase activity and alpha-xylosidase activity was shown to be classified in a middle position between alpha-glucosidase and alpha-xylosidase.
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PMID:Classification of some alpha-glucosidases and alpha-xylosidases on the basis of substrate specificity. 776 71

Two kojibiose-type pseudo-disaccharides and a trisaccharide, containing a 5-amino-1,2,3,4-cyclopentanetetrol derivative or valienamine, linked by way of nitrogen bridges to the sugar residues, have been designed and synthesized as processing alpha-glucosidase I inhibitors. Synthesis of the pseudo-disaccharides was carried out starting from the coupling products of the sugar isothiocyanates and an aminocyclitol, respectively, by cyclization with mercury(II) oxide to the cyclic isoureas and subsequent deprotection. Pseudokojibiose was prepared in a poor yield by reaction of a protected valienamine and a sugar epoxide, followed by deprotection. Although the pseudooligosaccharides are all strong inhibitors of alpha-glucosidase (baker's yeast), they did not have any inhibitory potency against either sucrase isomaltase (rat intestine) or processing alpha-glucosidase (rat liver microsomes).
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PMID:Synthesis of alpha-glucosidase inhibitors: kojibiose-type pseudo-disaccharides and a related pseudotrisaccharide. 965 66

alpha-D-Glucosylglycerol (GG) was found for the first time in sake (Japanese rice wine) in an amount of about 0.5%. GG was also found in miso and mirin which had been brewed by using koji. GG was hydrolyzed into glucose and glycerol in an equimolar ratio with maltase (EC 3.2.1.20, alpha-glucosidase from yeast), but not with emulsin (EC 3.2.1.21, beta-glucosidase from almond). The retention times and mass spectra of trimethylsilyl derivatives by a GC-MS analysis of GG in sake were comparable to those of various GG samples synthesized by glycol cleavage. It was proven that GG in sake consisted of three components, viz., 2-O-alpha-D-glucosyl-glycerol (GG-II), (2R)-1-O-alpha-D-glucosylglycerol (R-GG-I) and (2S)-1-O-alpha-D-glucosylglycerol (S-GG-I). The ratio of the three components in GG was 6:66:28 for sake. It is considered that GG was formed by transglucosylation of the glucosyl groups to glycerol by alpha-glucosidase from koji in the sake mash.
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PMID:Identification of alpha-D-glucosylglycerol in sake. 1073 96

Syzygium cumini seed kernel extracts were evaluated for the inhibition of alpha-glucosidase from mammalian (rat intestine), bacterial (Bacillus stearothermophilus), and yeast (Saccharomyces cerevisiae, baker's yeast). In vitro studies using the mammalian alpha-glucosidase from rat intestine showed the extracts to be more effective in inhibiting maltase when compared to the acarbose control. Since acarbose is inactive against both the bacterial and the yeast enzymes, the extracts were compared to 1-deoxynojirimycin. We found all extracts to be more potent against alpha-glucosidase derived from B. stearothermophilus than that against the enzymes from either baker's yeast or rat intestine. In an in vivo study using Goto-Kakizaki (GK) rats, the acetone extract was found to be a potent inhibitor of alpha-glucosidase hydrolysis of maltose when compared to untreated control animals. Therefore, these results point to the inhibition of alpha-glucosidase as a possible mechanism by which this herb acts as an anti-diabetic agent.
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PMID:Alpha-glucosidase inhibitory activity of Syzygium cumini (Linn.) Skeels seed kernel in vitro and in Goto-Kakizaki (GK) rats. 1837 20