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)

7 infants, aged 5 weeks to 11 months, with clinically documented intolerance to cow's milk protein, chronic diarrhea, and failure to thrive, underwent small intestinal (peroal, suction) biopsy before and after withdrawal of milk proteins. Mucosal specimens were examined by light microscopy and assayed for disaccharidase activities. In all patients, moderate to severe mucosal changes were presented, associated with marked inflammation of lamina propria and damages to the brushborder. Disaccharidase activities (lactase, sucrase, maltase and palatinase) were markedly depressed in all. Follow-up biopsies were obtained in 6 infants, after 3-5 months on a milk-protein-free diet. At the time of the second biopsy, the disaccharidase activities had risen significantly and histologic improvement had occurred in each instance. In infancy, intestinal mucosal lesions due to intolerance to cow's milk protein are histologically indistinguishable from those seen in gluten-sensitive enteropathy and are associated with marked secondary disaccharidase deficiencies. Following therapy, the activity of the disaccharidases become normal or near normal prior to the complete morphologic recovery of the small intestinal mucosa.
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PMID:Disaccharidase deficiency in infants with cow's milk protein intolerance. Response to treatment. 62 28

A close relationship exists between relative disaccharidase activities (maltase, sucrase, trehalase, palatinase, turanase, lactase, and cellobiase) in amniotic fluid and corresponding jejunal mucosa of five human fetuses (16 to 21 weeks of gestation) suggesting that these intestinal enzymes pass into amniotic fluid. Serial determination of disaccharidase activities in amniotic fluid samples collected between 10 and 42 weeks of gestation showed maximum mean activities at 14 to 17 weeks of gestation and a rapid drop to less than 12 per cent maximum values at about 22 weeks. This drop is probably caused by combined effects of decreased extrusion rate of intestinal disaccharidases and increased reabsorption of the enzymes in swallowed amniotic fluid with fetal development.
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PMID:Developmental patterns of intestinal disaccharidases in human amniotic fluid. 64 87

Disaccharidases activities in 20-day-old chick embryonic intestine were induced by the addition of sucrose, maltose, fructose and glucose to the culture medium. However, maltitol, which cannot be digested by intestinal enzymes, showed no effect on the induction of disaccharidase activity. Kinetic study of the enzymes demonstrated that the maximum velocity (Vmax) and the Michaelis constant (Km) of sucrose induced disaccharidases activities of the explants showed changes similar to those observed in the chick of same developmental stage in vivo. Namely, Vmax values of sucrase and maltase were increased. Km values of sucrase did not change, but that of maltase showed a significant decrease during development.
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PMID:Effect of various sugars on the induction of chick embryonic intestinal disaccharidases in the organ culture system. 69 Jul 28

Brush-border membranes were isolated from the rat small intestine and then treated with sodium dodecyl sulphate under non-reducing conditions at room temperature. Analysis of the solubilized components by polyacrylamide-gel electrophoresis identified three major glycoproteins that co-migrate with glucoamylase-maltase-sucrase, lactase and isomaltase-maltase-sucrase activities. High activities of alkaline phosphatase and trehalase were detectable, but they could not be attributed to distinct co-migrating protein bands. Analysis of mucosa from the distal small intestine by the same methods showed a pattern of bands different from that obtained with the proximal intestine, which appeared to correlate with the relative deficiency of some of the enzymes in the distal region.
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PMID:The identification of rat intestinal membrane enzymes after electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate. 69 63

1. Rats were fed with the elemental diet Vivonex for 1 or 3 months and their jejunal histology was compared with that of an equal number of rats fed on a normal diet. 2. After 1 month of Vivonex feeding a significant reduction in the ratio of crypt height: villus height (CH:VH) was found in the Vivonex-fed rats (n = 4) compared with the control rats (n = 4) (P less than 0.05). 3. After 3 months the CH:VH ratio was also reduced in the Vivonex-fed rats (n = 18) compared with control rats (n = 18) (P less than 0.002). Villus height was significantly increased (P less than 0.002) and crypt height decreased (P less than 0.05). 4. Jejunal protein content, alkaline phosphatase and disaccharidase activity were also determined in 12 control and 12 Vivonex-fed rats from the 3 months study. 5. Alkaline phosphatase activity was increased from a control value of 201 +/- 8 to 243 +/- 15 munits/cm in the Vivonex-fed rats (n = 12) (P less than 0.05) but no significant changes in lactase, sucrase or maltase activites were found. The observed decrease in the CH:VH ratio suggested an improved survival of the mature enterocyte population during elemental diet feeding.
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PMID:Small-intestinal changes induced by an elemental diet (Vivonex) in normal rats. 72 6

It was taken 32 male Wistar rats, weighting between 130 g and 150 g, free feeding, to study the total and specific activities of lactase, invertase and maltase of small intestine of rats. The animals were divided by chance in 3 experimental and 1 control group. 1. group--Aloxanic diabetes rats: treated with 1 unit of NPH insulin every day: after the 4th day of aloxane administration, all rats were killed. 2. group--Aloxanic diabetes rats--treated for 5 days with 1 unit of NPH insulin every day; after the 5th day until the 7th they were treated with 4 units of NPH insulin and were also killed. 3. group--Hyperinsulinism rats--Normal rats were treated for 4 days with 4 units of NPH insulin every day. After the 5th day they were killed. 4. group--Control group--Normal rats, free feeding. They were observed during 4 days and were also killed. The results showed that none difference was observed in the 4 groups of rats about the total and specific activities of lactase, invertase and maltase of the small intestine. In this study, all the animals with aloxanic diabetes were treated with insulin. Then, it is possible that the insulin inhibited the stimulator effect of the diabetes upon the dissacaridases of the small intestine of the rats.
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PMID:[Insulin and disaccharidases levels of the small intestine of the rat (author's transl)]. 74 51

The role of mitochondria in carbon catabolite repression in Saccharomyces cerevisiae was investigated by comparing normal, respiratory competent (RHO) strains with their mitochondrially inherited, respiratory deficient mutant derivatives (rho). Formation of maltase and invertase was used as an indicator system for the effect of carbon catabolite repression on carbon catabolic reactions. Fermentation rates for glucose, maltose and sucrose were the same in RHO and rho strains. Specific activities of maltase and invertase were usually higher in the rho-mutants. A very pronounced difference in invertase levels was observed when cells were grown on maltose; rho-mutants had around 30 times more invertase than their RHO parent strains. The fact that rho-mutants were much less sensitive to carbon catabolite repression of invertase synthesis than their RHO parents was used to search for the mitochondrial factor(s) or function(s) involved in carbon catabolite repression. A possible metabolic influence of mitochondria on this system of regulation was tested after growth of RHO strains under anaerobic conditions (no respiration nor oxidative phosphorylation), in the presence of KCN (respiration inhibited), dinitrophenol (uncoupling of oxidative phosphorylation) and of both inhibitors anaerobic conditions and dinitrophenol had no effect on the extent of invertase repression. KCN reduced the degree of repression but not to the level found in rho-mutants. A combination of both inhibitors gave the same results as with KCN alone. Erythromycin and chloramphenicol were used as specific inhibitors of mitochondrial protein synthesis. Erythromycin prevented the formation of mitochondrial respiratory systems but did not induce rho-mutants under the conditions used. However, repression of invertase was as strong as in the absence of the inhibitor. Chloramphenicol led only to a slight reduction of the respiratory systems and did not affect invertase levels. A combination of both antibiotics had about the same effect as growth in the presence of KCN. The results showed that mitochondria are involved in carbon catabolite repression and they cause an increase in the degree of repression. These effects cannot be due to mere metabolic activities nor to factors made on the mitochondrial protein synthesizing machinery. This regulatory role of mitochondria is observed as long as an intact mitochondrial genome is maintained.
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PMID:The role of mitochondria in carbon catabolite repression in yeast. 79 Jan 58

Sucrase-isomaltase complex and its functional subunits have been identified in homogenates of human small intestinal mucosa by use of Sephadex G-200 (superfine) chromatography aided by affinity of the isomaltase moiety for the dextran gel. The isomaltase subunit binds strongly to the gel at 4 degrees, and is eluted only after 2 column volumes; earlier recovery as a sharp peak can be achieved by raising column temperature to 37 degrees after elution of other proteins. Bio-Gel P-300 chromatography, density gradient, and equilibrium centrifugation demonstrated that the sucrase subunit (Stokes radius = 45 A, frictional ratio = 1.32, s20,w = 6.9, MW = 130,000) and the isomaltase subunit (Stokes radius = 45 A, frictional ratio = 1.30, s20,w = 6.6, MW = 120,000) are similar but unequal in size. The sucrase-isomaltase complex (Stokes radius = 70 A, frictional ratio = 1.61, s20,w = 9.8, MW = 280,000), appears to be an elongated hybrid molecule that is less symmetrical than either of itt subunits. Apparent Km and pH activity curves were indistinguishable for each enzyme whether present in the hybrid or in the free state. The sucrase-isomaltase complex, accounting for approximately 90 percent of native intestinal sucrase and isomaltase activities, was isolated and cleaved by 0.01 M beta-mercaptoethanol/6 M urea treatment into active sucrase and isomaltase subunits having biochemical characteristics identical with those of the free native moieties. Sodium dodecyl sulfate acrylamide gell electrophoresis of the complex also produced subunits having molecular weights very close to those for the active free sucrase and isomaltase moieties, indicating that each alpha-glucosidase appears to consist of a single polypeptide chain. Immunization of rabbits with pure sucrase-isomaltase complex yielded a monospecific precipitating antibody that reacted with the hybrid and the sucrase subunit, but had minimal affinity for the isomaltase subunit, providing further evidence that the sucrase-isomaltase molecule is a hybrid consisting of two distinct alpha-glucosidases.
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PMID:Human intestinal sucrase-isomaltase. Identification of free sucrase and isomaltase and cleavage of the hybrid into active distinct subunits. 80 75

Two therapeutic regimens were compared in 16 infants with protracted diarrhea and malnutrition. Eight patients were treated with total parenteral nutrition given via a central vein (group A); the remaining eight patients received a combination of dilute parenteral nutrients given in a peripheral vein plus continuous enteral feedings of an elemental diet (group B). All patients recovered although two infants in group B were switched to TPN treatment after a poor response to the elemental diet. Intestinal biopsies were performed: (1) before treatment; (2) after 2 to 3 weeks of TPN or elemental diet; and (3) after 2 to 3 weeks of Nutramigen feedings. Before treatment, all patients had atrophic changes in the jejunal epithelium and deficient disaccharidase and trypsin activities. The second biopsy showed morphologic recovery in all patients, incomplete recovery of lactase and trypsin in both treatment groups, and complete recovery of sucrase and maltase activities only in group B patients. The third biopsy showed normal morphology and complete recovery of all enzymes measured. The mean number of hospital days was 46 +/- 4.8 for group A and 34 +/- 1.6 for group B (p less than 0.05) suggesting that patients given enteral feedings early tended to have a more rapid return of intestinal function and of some intestinal enzymes.
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PMID:Protracted diarrhea and malnutrition in infancy: Changes in intestinal morphology and disaccharidase activities during treatment with total intravenous nutrition or oral elemental diets. 81 May 53

The effect of 8-hydroxyquinoline, a rapid inhibitor of RNA synthesis, was followed on the activity of a number of enzymes in cultures of the fission yeast Schizosaccharomyces pombe. Two types of effect were found. In the first the activity continued to rise for a period and then remained constant. This occurred with alkaline phosphatase, basal and derepressed acid phosphatase, hexokinase, and derepressed sucrase and maltase at low cell density. It is consistent with control being exercised by an unstable mRNA or by an unstable stimulator of translocation. In the second the activity increased above the control values for several hours. This occurred with basal sucrase and maltase, and suggests a stable mRNA and an unstable inhibitor of translation. The extent of 'superproduction' of sucrase varied with cell density and with growth medium and this may be due to differences in the degree of translational inhibition. The possiblilty of a stable mRNA has interesting implications for the control of enzyme synthesis through the cell cycle.
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PMID:The effect of 8-hydroxyquinoline on enzyme synthesis in the fission yeast Schizosaccharomyces pombe. 81 99


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