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)

Since they are found to be increased in lesions of acute necrotic ulcerative gingivitis or marginal periodontitis, agents for these diseases. In the present study, 38 pure cultured strains were obtained as a result of isolation and culture of samples collected from lesions of marginal periodontitis (periodontal pokets), and the biological and biochemical characteristics of these strains were investigated. 1) Light microscopy (including dark-field microscopy) and transmission electron microscopy (negative staining) were used for observation of the morphology and cellular structure of the strains. The cells had a spiral shape, and showed active movement. Based on the above findings the cultured strains were all confirmed to be spirochetes of small to medium size, being 0.08-0.24 micron in width. 2) Growth and motility of the strains were investigated on various types of culture medium. Intense growth and movement were noted in strains cultured in bovine liver exudate medium containing horse serum (pH 7.2) at 37 degrees C under anaerobic conditions produced by the evacuation-replacement method (95% N2, 5% CO2) for 3-7 days after inoculation. 3) Thirty-five strains were positive for indole production and decomposition of urea, mucin, hippuric acid and esculin. Production of hydrogen sulfied was observed in 31 strains. In decomposition tests for 17 carbohydrates, 17 strains were positive for galactose and 14 strains were positive for glucose, while 11 strains were positive for dextrin and 10 strains for fructose upon decomposition of soluble starch. Other carbohydrates were also decomposed by a few strains. 4) In an investigation of the production of alcohol and lower fatty acids, among the metabolic products detected by gas chromatography, a large amount of acetic acid and small amounts of ethanol, lactic acid, propionic acid, pyruvic acid were observed. 5) The results of enzyme activity tests using an API ZYM system indicated relatively high activities of esterase, esterase-lipase, alpha-glucosidase, alkaline phosphatase, trypsin and acid phosphatase.
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PMID:[Biological and biochemical characteristics of the oral spirochetes isolated from the focus of marginal periodontitis]. 276 48

Crystalline Aspergillus niger alpha-glucosidase and highly purified preparations of rice alpha-glucosidase II and Trichoderma reesei trehalase were found to catalyze the hydration of [2-(2)H]-D-gluco-octenitol, i.e., (Z)-3,7-anhydro-1,2-dideoxy-[2-2H]-D-gluco-oct-2-enitol, to yield 1,2-dideoxy-[2-2H]-D-gluco-octulose. In each case, the stereochemistry of the reaction was elucidated by examining the newly formed centers of asymmetry at C-2 and C-3 of the hydration product. The C-1 to C-3 fragment of each isolated [2-2H]-D-gluco-octulose product was recovered as [2-2H]propionic acid and identified by its positive optical rotatory dispersion as the S isomer, showing that each enzyme had protonated the octenitol (at C-2) from above its re face. 1H NMR spectra of enzyme/D-gluco-octenitol digests in D2O showed that the alpha-anomer of [2-2H]-D-gluco-octulose was exclusively produced by each alpha-glucosidase, whereas the beta-anomer was formed by action of the trehalase. The trans hydration catalyzed by the alpha-glucosidases was found to be very strongly inhibited by the substrate; the cis hydration reaction catalyzed by the trehalase showed no such inhibition. Special importance is attached to the finding that in hydrating octenitol each enzyme creates a product of the same anomeric form as in hydrolyzing an alpha-D-glucosidic substrate. This result adds substantially to the growing evidence that individual glycosylases create the configuration of their reaction products by a means that is independent of donor substrate configuration, that is, by a means other than "retaining" or "inverting" substrate configuration.
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PMID:Steric course of the hydration of D-gluco-octenitol catalyzed by alpha-glucosidases and by trehalase. 328 13

A comprehensive study was performed on 25 bacterial clinical isolates originally identified as Corynebacterium xerosis. Three reference strains of C. xerosis were also included in the study. On the basis of a variety of phenotypic characteristics tested, all strains could be divided into two separate clusters: reference strains ATCC 373 (the type strain of C. xerosis) and ATCC 7711 showed yellow-pigmented, dry, rough colonies, fermented 5-keto-gluconate, exhibited strong leucine arylamidase and alpha-glucosidase activities, produced lactate as the major end product of glucose metabolism, were susceptible to most of the 19 antimicrobial agents tested, and showed an inhibition zone around disks containing the vibriocidal compound O/129. In contrast, the remaining 26 strains including reference strain NCTC 7243 as well as all clinical isolates formed white-grayish, dry, slightly rough colonies, did not ferment 5-keto-gluconate, exhibited only weak leucine arylamidase and no alpha-glucosidase activity, produced large amounts of propionic acid as the end product of glucose metabolism, and were resistant to most antimicrobial agents tested, including O/129. Chemotaxonomic (cellular fatty acids, mycolic acids, and G+C content) and molecular genetic (16S rRNA gene sequence) investigations revealed that the strains of the second cluster unambiguously belonged to the species C. amycolatum. Our data suggest that most strains reported in the literature as C. xerosis are probably misidentified and correspond to C. amycolatum.
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PMID:Most Corynebacterium xerosis strains identified in the routine clinical laboratory correspond to Corynebacterium amycolatum. 872 88

Up to now, the metabolism of hispidulin (5,7,4'-trihydroxy-6-methoxyflavone), a potent ligand of the central human benzodiazepine receptor, has not been investigated. To elucidate the metabolism of hispidulin in the large intestine, its biotransformation by the pig caecal microflora was studied. In addition, the efficiency of the pig caecal microflora to degrade galangin (3,5,7-trihydroxyflavone), kaempferol (3,5,7,4'-tetrahydroxyflavone), apigenin (5,7,4'-trihydroxyflavone), and luteolin (5,7,3',4'-tetrahydroxyflavone) was investigated. Identification of the formed metabolites was performed by high-performance liquid chromatography (HPLC)-diode array detection, HPLC-electrospray ionization-tandem mass spectrometry, and high-resolution gas chromatography-mass spectrometry. The caecal microflora transformed hispidulin to scutellarein (5,6,7,4'-tetrahydroxyflavone), an effective alpha-glucosidase inhibitor, and 3-(4-hydroxyphenyl)-propionic acid; galangin to phenylacetic acid and phloroglucinol; kaempferol to 4-hydroxyphenylacetic acid, phloroglucinol, and 4-methylphenol; apigenin to 3-(4-hydroxyphenyl)-propionic acid and 3-phenylpropionic acid, and luteolin to 3-(3-hydroxyphenyl)-propionic acid, respectively. To elucidate to what extent different hydroxylation patterns on the B-ring influence the degradation degree of flavonoids, the conversions of galangin and kaempferol as well as that of apigenin and luteolin were compared with those of quercetin (3,5,7,3',4'-pentahydroxyflavone) and chrysin (5,7-dihydroxyflavone), respectively. Regardless of the flavonoid subclass, the presence of a hydroxy group at the 4'-position seems to be a prerequisite for fast breakdown. An additional hydroxy group at the B-ring did not affect the degradation degree.
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PMID:Use of the pig caecum model to mimic the human intestinal metabolism of hispidulin and related compounds. 1631 85