Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A synthetic beta-thio-fructofuranoside of mercaptoethanol inhibited not only beta-fructofuranosidases but also alpha-glucosidases. The compound was hardly hydrolyzed by the glycosidases. The thio-fructoside competitively inhibited beta-fructofuranosidases from Aspergillus niger, Candida sp., and Saccharomyces cerevisiae, but not Arthrobacter beta-fructofuranosidase at all. Sucrase activity of rat intestinal sucrase/isomaltase complex was also suppressed in the presence of the thio-fructoside. The thio-fructoside showed noncompetitive inhibition toward maltase activity of the rat intestinal enzyme complex and Saccharomyces sp. alpha-glucosidase. Inhibition against the Bacillus stearothermophilus alpha-glucosidase, Rhizopus glucoamylase, and porcine kidney trehalase were more slight than that against these two alpha-glucosidases.
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PMID:Inhibition of beta-fructofuranosidases and alpha-glucosidases by synthetic thio-fructofuranoside. 1295 5

The invertase-encoding of AINV gene Arxula adeninivorans was isolated and characterized. The gene includes a coding sequence of 2700 bp encoding a putative 899 amino acid protein of 101.7 kDa. The identity of the gene was confirmed by a high degree of homology of the derived amino acid sequence to that of alpha-glucosidases from different sources. The gene activity is regulated by carbon source. In media supplemented with sucrose induction of the AINV gene and accumulation of the encoded invertase in the medium was observed. In addition the extracellular enzyme level is influenced by the morphological status of the organism, with mycelia secreting the enzyme in titres higher than those observed in budding yeasts. The enzyme characteristics were analysed from isolates of native strains as well as from those of recombinant strains expressing the AINV gene under control of the strong A. adeninivorans -derived TEF1 promoter. For both proteins a molecular mass of 600 kDa was determined, a pH optimum at pH 4.5 and a temperature optimum at 55 degrees C. The preferred substrates for the enzyme included the ss-D-fructofuranosides sucrose, inulin and raffinose. Only a weak enzyme activity was observed for the alpha-D-glucopyranosides maltotriose, maltose and isomaltose. Thus the invertase primarily is a ss-fructosidase and not an alpha-glucosidase as suggested by the homology to such enzymes.
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PMID:Characterization of the AINV gene and the encoded invertase from the dimorphic yeast Arxula adeninivorans. 1528 Jun 46

The suppressive effect on the postprandial blood glucose rise through alpha-glucosidase (AGH) inhibition was investigated in this study in order to clarify an antihyperglycemic function of 6-O-caffeoylsophorose (CS) from diacylated anthocyanin. The administration of CS (100 mg/kg) following maltose (2 g/kg) to Sprague-Dawley rats resulted in the maximal blood glucose level after 30 min being significantly decreased by 11.1% compared to the control. A reduction in the serum insulin secretion was also observed in parallel to the decrease in blood glucose level. No blood glucose change was apparent when sucrose or glucose was ingested, suggesting that the antihyperglycemic effect of CS was achieved by maltase inhibition, rather than by sucrase or glucose transport inhibition. An AGH inhibitory assay demonstrated that the non-competitive maltase inhibition of CS was partly due to acylation by phenolic acid with sugar, the presence of hydroxyl groups in the aromatic ring, and the presence of an unsaturated alkyl chain in the acylated moiety.
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PMID:Caffeoylsophorose, a new natural alpha-glucosidase inhibitor, from red vinegar by fermented purple-fleshed sweet potato. 1556 60

A beta-fructosidase (EC 3.2.1.26) was isolated from the midgut of larval sugar cane stalk borer Diatraea saccharalis by mild-denaturing electrophoresis and further purified to near homogeneity by gel filtration. beta-Fructosidase hydrolysed sucrose, raffinose and the fructosyl-trisaccharide isokestose, but it had no activity against maltose, melibiose and synthetic substrates for alpha-glucosidases. Two other sucrose hydrolases, one resembling a alpha-glucosidase (EC 3.2.1.20) and the other one active specifically against sucrose (sucrase) were detected in the larval midgut of D. saccharalis. All three sucrose hydrolases were associated with the midgut epithelium of larval D. saccharalis. Relative molecular mass (M(r)) of the beta-fructosidase was estimated around 45,000 (by gel filtration). The other two sucrose hydrolases had M(r) of 54,000 (alpha-glucosidase) and 59,000 (sucrase). The pH optima of the sucrose hydrolases were 5-10 for both alpha-glucosidase and sucrase and 7-8 for beta-fructosidase. Considering V(max)/K(m) ratios, beta-fructosidase preferentially cleaves isokestose rather than raffinose and sucrose. In order to evaluate the possible contribution of microorganisms isolated from the midgut to the pool of sucrose hydrolases, washed midgut epithelia were homogenised and plated onto appropriate media. Seven bacterial and one yeast species were isolated. None of the sucrose hydrolases extracted from the microorganisms corresponded to the enzymes isolated from midgut tissue homogenates. This result suggests that the major sucrose hydrolases found in the midgut of larval D. saccharalis were probably produced by the insect themselves not by the gut microflora.
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PMID:Sucrose hydrolases from the midgut of the sugarcane stalk borer Diatraea saccharalis. 1560 12

A hot water extract obtained by boiling adzuki beans (Vigna angularis) to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. The IC(50) values for each hydrolylase were 0.78 mg/ml (alpha-amylase), 2.45 mg/ml (maltase), 5.37 mg/ml (sucrase), and 1.75 mg/ml (isomaltase). The active fraction showed potential hypoglycemic activity in both normal mice and streptozotocin (STZ)-induced diabetic rats after an oral administration of sucrose, but did not show any effect on the blood glucose concentration after glucose administration, suggesting that the active fraction suppressed the postprandial blood glucose level by inhibiting alpha-glucosidase and alpha-amylase, irrespective of the endogenous blood insulin level.
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PMID:Suppressive effect of a hot water extract of adzuki beans (Vigna angularis) on hyperglycemia after sucrose loading in mice and diabetic rats. 1561 10

We designed and synthesized polyhydroxylated pyrrolidines 1-12 from L-tyrosine, L-phenylalanine, and D-tyrosine through iodine-mediated intramolecular cyclization followed by Woodward-Prevost reaction. The synthetic polyhydroxylated pyrrolidines were identified with structure-based inhibitory activity and selective inhibitory activity against alpha-rhamnosidase. (2S,3S,4R)-deacetyl anisomycin 7 was the best inhibitor among the 12 polyhydroxylated pyrrolidines because it possesses the same stereoconfiguration at C1, C2, C3 as alpha-L-rhamnopyranoside. An investigation into the nature of the inhibition showed that the synthetic pyrrolidines are competitive inhibitors. They also did not have remarkable inhibitory activity against seven glycosidases (alpha-glucosidase, alpha-mannosidase, alpha-amylase, beta-glucosidase, beta-galactosidase, beta-amylase, and invertase).
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PMID:Alpha-rhamnosidase inhibitory activities of polyhydroxylated pyrrolidine. 1603 52

The osmotic pressure of the body fluids of aphids is lower than in their diet of plant phloem sap. It is hypothesised that aphids reduce the osmotic pressure of ingested food by sucrase-mediated hydrolysis of dietary sucrose to glucose and fructose, and the polymerisation of glucose into oligosaccharides of low osmotic pressure per hexose unit. To test this hypothesis, the impact of the alpha-glucosidase inhibitor acarbose on the sugar relations and osmoregulation of aphids was explored. Acarbose inhibited sucrase activity in gut homogenates and the production of monosaccharides and oligosaccharides in the honeydew of live aphids. Acarbose caused an increase in the haemolymph osmotic pressure for aphids reared on a diet (containing 0.75 M sucrose) hyperosmotic to the haemolymph and not on the isoosmotic diet containing 0.2 M sucrose. It did not affect aphid feeding rate over 2 days, except at high concentrations on 0.75 M sucrose diet, and this may have been a secondary consequence of osmotic dysfunction. Acarbose-treated aphids died prematurely. With 5 microM dietary acarbose, mean survivorship on 0.2 M sucrose diet was 4.2 days, not significantly different from starved aphids, indicating that, although these aphids fed, they were deprived of utilisable carbon; and on 0.75 M sucrose diet, mean survivorship was just 2.8 days, probably as a consequence of osmotic failure. It is concluded that the aphid gut sucrase activity is essential for osmoregulation of aphids ingesting food hyperosmotic to their body fluids.
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PMID:The significance of gut sucrase activity for osmoregulation in the pea aphid, Acyrthosiphon pisum. 1616 4

Alkyl glycosides are interesting intermediates for the production of biodegradable surfactants. Synthesis of ethyl beta-d-fructofuranoside by invertase-catalysed ethanolysis of sucrose has been extensively reported in literature. However, this procedure yields mixtures of glucose, fructose, sucrose and ethyl beta-d-fructofuranoside. Purification of ethyl beta-d-fructofuranoside from such mixtures by chromatographic methods is laborious, difficult to scale up and requires organic solvents. The yeast Hansenula polymorpha grows rapidly on glucose, fructose and sucrose. Sucrose hydrolysis in this yeast is catalysed by an intracellular alpha-glucosidase ('maltase'); consequently, H. polymorpha should be unable to hydrolyse ethyl beta-d-fructofuranoside. Indeed, aerobic cultivation of H. polymorpha on sugar mixtures obtained by invertase-catalysed ethanolysis of sucrose resulted in the complete removal of contaminating sugars, leaving ethyl beta-d-fructofuranoside as the sole organic compound in culture supernatants. Pure ethyl beta-d-fructofuranoside was recovered from the supernatants by mixed-bed ion exchange chromatography with an 86% yield.
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PMID:Use of the yeast Hansenula polymorpha (Pichia angusta) to remove contaminating sugars from ethyl beta-D-fructofuranoside produced during sucrose ethanolysis catalysed by invertase. 1623 29

The global gene expression of cultured Saccharomyces cerevisiae protoplasts was compared with that of cells using DNA microarray. Quantitative and qualitative analyses revealed that after 6 h of cultivation, 416 gene transcript levels (about 7.1% in all) in the cultured protoplasts were different from those in the cells. Various characteristics and functions of the protoplasts were predicted from the analysis of the gene functions. The cultured protoplasts were more sensitive to oxidative stress than the cultured cells. Their cell cycles were arrested at the G1 phase and cell wall synthesis was promoted. Carbohydrate metabolism was activated in cultured protoplasts, while amino acid biosynthesis was inhibited. Furthermore, some genes associated with the secretory pathway of metabolites were activated, leading to active secretion of these metabolites into the broth. As an example of the application of DNA microarray analysis, we developed two novel methods for the production of useful enzymes based on the characteristics of protoplasts. One was the production of invertase based on the activated secretory pathway, while the other was the production of alpha-glucosidase based on the activated carbohydrate metabolism. The secretion of invertase and alpha-glucosidase was promoted in cultured protoplasts. The invertase and alpha-glucosidase productivities in the cultured protoplasts were 657 U and 218 U, respectively. On the other hand, only 227 U of invertase was produced, while alpha-glucosidase was not detected, in the cultured cells. The fragile protoplasts were immobilized in agarose gel to protect them from hydrodynamic stress. Four repeated-batch cultures with the immobilized protoplasts were performed, leading to the production of 1574 U of invertase and 739 U of alpha-glucosidase. The same productivities were obtained when this system was scaled up by 10-fold (invertase: 13304 U; alpha-glucosidase: 7688 U).
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PMID:Analysis of gene expression in yeast protoplasts using DNA microarrays and their application for efficient production of invertase and alpha-glucosidase. 1623 11

Intracellular products, not secreted from the microbial cell, are released by breaking the cell envelope consisting of cytoplasmic membrane and an outer cell wall. Hydrodynamic cavitation has been reported to cause microbial cell disruption. By manipulating the operating variables involved, a wide range of intensity of cavitation can be achieved resulting in a varying extent of disruption. The effect of the process variables including cavitation number, initial cell concentration of the suspension and the number of passes across the cavitation zone on the release of enzymes from various locations of the Brewers' yeast was studied. The release profile of the enzymes studied include alpha-glucosidase (periplasmic), invertase (cell wall bound), alcohol dehydrogenase (ADH; cytoplasmic) and glucose-6-phosphate dehydrogenase (G6PDH; cytoplasmic). An optimum cavitation number Cv of 0.13 for maximum disruption was observed across the range Cv 0.09-0.99. The optimum cell concentration was found to be 0.5% (w/v, wet wt) when varying over the range 0.1%-5%. The sustained effect of cavitation on the yeast cell wall when re-circulating the suspension across the cavitation zone was found to release the cell wall bound enzyme invertase (86%) to a greater extent than the enzymes from other locations of the cell (e.g. periplasmic alpha-glucosidase at 17%). Localised damage to the cell wall could be observed using transmission electron microscopy (TEM) of cells subjected to less intense cavitation conditions. Absence of the release of cytoplasmic enzymes to a significant extent, absence of micronisation as observed by TEM and presence of a lower number of proteins bands in the culture supernatant on SDS-PAGE analysis following hydrodynamic cavitation compared to disruption by high-pressure homogenisation confirmed the selective release offered by hydrodynamic cavitation.
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PMID:Disruption of Brewers' yeast by hydrodynamic cavitation: Process variables and their influence on selective release. 1657 Mar 16


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