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)

Calf pancreas microsomes incorporated radioactively labeled D-glucose from UDP-D-glucose into products extracted with chloroform/methanol (2:1, v/v), chloroform/methanol/water (10:102.5, v/v), and into the residual precipitate, with a pH optimum in Tris/maleate buffer of about 5.3. The chloroform/methanol extract contained a single 14C-labeled acidic product, which was identified as dolichyl beta-D-glucosyl phosphate. It was stable to mild alkali, yielded D-[14C]glucose upon mild acid hydrolysis, and a 14C-labeled compound with the chromatographic mobility of 1,6-anhydro-beta-D-glucopyranosyl upon hot alkali treatment. The [14C]glucolipid had the same chromatographic mobility as dolichyl beta-D-[14C]mannosyl phosphate, and its formation was stimulated by exogenous dolichyl phosphate. The chloroform/methanol/water extract contained radioactive lipid-bound oligosaccharides which were retained on DEAE-cellulose more strongly than dolichyl D-[14C]glucosyl phosphate. They were stable to mild alkali, but labile to acid and hot alkali. Acid treatment yielded a D-glucose-labeled oligosaccharide fraction which was shown by gel filtration to be slightly larger than most of the D-mannose-labeled oligosaccharides. About 80% of the radioactive D-glucose residues could be removed with alpha-glucosidase, but not with beta-glucosidase. Pancreatic dolichyl beta-D-[14C]glucosyl phosphate incubated with calf pancreas microsomes served as direct donor of D-glucosyl residues to lipid-bound oligosaccharides and to the precipitate. These oligosaccharides had the same size as those labeled from UDP-D-[14C]glucose, and the D-[14C]glucose residues could also be removed with alpha-glucosidase.
 ...
PMID:Glucosyltransferase activity in calf pancreas microsomes. Formation of dolichyl D[14C]glucosyl phosphate and 14C-labeled lipid-linked oligosaccharides from UDP-D-[14C]glucose. 84 29

Mouse peritoneal macrophages that had been treated with a monovalent carboxylic ionophore, monensin, selectively secreted lysosomal and nonlysosomal granular enzymes into the medium. When macrophages were incubated with 1 to 10 microM monensin, the release of beta-glucuronidase, beta-hexosaminidase and beta-galactosidase was stimulated time and does dependently. Neither the beta-glucosidase nor acid phosphatase, enzymes bound to the lysosomal membranes, however, were released by monensin. Neutral alpha-glucosidase, shown recently to be localized in nonlysosomal granules of macrophages (15), was released by monensin at concentrations lower than those required for lysosomal enzyme release. Increased release of lysosomal enzymes also took place in a manner similar to that seen with monensin-treated macrophages after treatment of macrophages with weak bases, chloroquine and ammonium chloride. Neutral alpha-glucosidase, however, was not released when chloroquine was present in concentrations that stimulated the release of lysosomal enzymes. The UDP-galactosyltransferase activity of the Golgi apparatus in the macrophages markedly decreased after treatment with low concentration of monensin.
 ...
PMID:Stimulation of the release of lysosomal and nonlysosomal granular enzymes from macrophages treated with monensin. 643 21

The activities of various enzymes involved in detoxication and carbohydrate metabolism in the liver and the gastrointestinal tract of germfree (GF) and conventional (CV) rats, 8 and 40 weeks' old, were measured in relationship to intestinal microflora and aging. In 8-week-old rats, the activities of nitroreductase (NR) and aniline hydroxylase (AH) in the liver, and of alkaline phosphatase (ALP), maltase and lactase in the duodenum were higher in GF than in CV rats, but the activities of arginosuccinate synthetase (ASS) and lactate dehydrogenase (LDH) in the liver were higher in CV than in GF rats. In 40-week-old rats, the activities of NR and glucose-6-phosphatase dehydrogenase (G-6-PDH) of the liver and ALP, maltase and lactase of the duodenum were higher in GF than in CV rats, but those of ASS, UDP-glucuronyl transferase (UDP-GT), AH, beta-glucuronidase, and LDH of the liver were higher in CV than in GF rats. Compared between 8- and 40-week-old rats the activities of NR, beta-glucuronidase, LDH, and acid phosphatase increased with aging in both GF and CV rats. The specific activities of ASS in CV and UDP-GT and AH in GF rats decreased with aging. The total activities of ASS and AH in GF rats also decreased with aging. The activities of ALP, maltase and lactase decreased with aging in both GF and CV rats. Thus, these data suggested that there are influences of indigenous intestinal microflora and aging on the activities of various enzymes in the liver and gastrointestinal tract.
 ...
PMID:Intestinal microflora and aging: age-related change of enzymes in the liver and the small intestine of germ-free and conventional rats. 679 85

The syntheses of two ammonium salts of 1,4-dideoxy-1,4-imino-d-galactitol containing erythritol sulfate side chains are described. The parent compound is a known inhibitor of the enzyme UDP-galactopyranose mutase (UDP-galactopyranose furanomutase, E.C. 5.4.99.9), which is responsible for the conversion of UDP-galactopyranose into UDP-galactofuranose and is presumably protonated in its active form. The side chain was chosen because it is present in a known sulfonium ion alpha-glucosidase inhibitor, salacinol. The syntheses of the selenonium analogues derived from 1,4-dideoxy-1,4-seleno-d-galactitol are also described. The synthetic strategy in the syntheses of all four salts involved the nucleophilic attack of a protected derivative of the alditol at the least hindered carbon of 2,4-O-benzylidene d- or l-erythritol-1,3-cyclic sulfate to give adducts that were subsequently deprotected. The importance of different protecting groups used in the various syntheses is also highlighted. Enzyme inhibition assays carried out on these compounds, and the corresponding sulfonium ions synthesized previously, show that they are poor inhibitors of UDP-galactopyranose mutase.
 ...
PMID:Synthesis of novel ammonium and selenonium ions and their evaluation as inhibitors of UDP-galactopyranose mutase. 1533 48