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)

Microbial beta-fructofuranosidases with transfructosylating activity can catalyze the transfructosylation of sucrose and synthesize fructooligosaccharides. Aspergillus japonicus NTU-1249 isolated from natural habitat was found to produce a significant amount of beta-fructofuranosidase with high transfructosylating activity and to have the potential for industrial production of fructooligosaccharides. In order to improve it's enzyme productivity, the medium composition and the cultivation conditions for A. japonicus NTU-1249 were studied. A. japonicus NTU-1249 can produce 83.5 units of transfructosylating activity per ml broth when cultivated in a shaking flask at 28 degrees C for 72 hours with a modified medium containing 80 g/l sucrose, 15 g/l soybean flour, 5 g/l yeast extract and 5 g/l NaCl at an initial pH of 6.0. The enzyme productivity was also optimized by submerged cultivation in a 5-litre jar fermentor with aeration at 1.5 vvm and agitation at 500 rpm. Under these operating conditions, the productivity of transfructosylating activity increased to 185.6 U/ml. Furthermore, the transfructosylating activity was improved to 256.1 U/ml in 1,000-litre pilot-scale fermentor. Enzymatic synthesis of fructooligosaccharides by beta-fructofuranosidase from A. japonicus NTU-1249 was performed in batch type by adding 5.6 units of transfructosylating activity per gram of sucrose to a 50% (w/v) sucrose solution at pH 5.0 and 50 degrees C. The yield of fructooligosaccharides was about 60% after reaction for 24 hours, and the syrup produced contained 29.8% (w/v) fructooligosaccharides, 15.2% (w/v) glucose and 5.0% (w/v) sucrose.
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PMID:Production of beta-fructofuranosidase with transfructosylating activity for fructooligosaccharides synthesis by Aspergillus japonicus NTU-1249. 181 45

A disturbance of the integrity of the intestinal epithelium with an increased risk for bacterial translocation is one of the suggested factors underlying the increased incidence of infections and septicaemia during vitamin A deficiency. In the present study the effects of vitamin A deficiency on the enzymic activity of enterocytes in response to bacterial colonization with a non-pathogenic Escherichia coli strain were studied in monocolonized and conventional Wistar rats. The monocolonized, but not the conventional, vitamin A-deficient rats had markedly reduced weight compared to their pair-fed controls and presented neurological symptoms, such as hind leg weakness, tremor and slow gait. Moreover, only in the monocolonized vitamin A-deficient rats were severe diarrhoea and bacterial translocation to extraintestinal sites-mainly kidneys-detected. Measurements of enterocyte brush-border enzyme activities revealed that lactase, sucrase, gamma-glutamyltranspeptidase (GGT) and dipeptidyl peptidase IV (DPP IV) were significantly reduced in the monocolonized vitamin A-deficient rats compared to the pair-fed controls, indicating a severe functional disturbance of the enterocytes. In conventional vitamin A-deficient rats only sucrase activity was markedly lower than in the respective controls. Our observation, that the deficient vitamin A status led to a strong reduction of enterocyte enzymic activities, associated with diarrhoea and increased bacterial translocation, mainly in the gnotobiotic rats, suggests that the composition of the bacterial flora, i.e. the colonization state, has a strong influence on triggering the severity of the functional disturbances of the intestinal epithelium, and adds to the clinical manifestations of vitamin A deficiency.
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PMID:Vitamin A deficiency leads to severe functional disturbance of the intestinal epithelium enzymes associated with diarrhoea and increased bacterial translocation in gnotobiotic rats. 1273 96

Water droplets or mist occur naturally in the air at seashores. These water droplets carry inorganic and organic substances from the sea to the land via the air, creating fertile land in sandy coastal areas (1). The same phenomenon occurs in an air-fluidized bed bioreactor (2). In an air-fluidized bed reactor, proteins can be transferred from the bioreactor semisolid bulk phase to an enriched droplet phase. This protein transfer process (droplet fractionation) can be experimentally simulated by shaking a separatory funnel containing a dilute solution of a given protein, which can be an enzyme like invertase. The created droplets become richer in invertase (protein) than that of the original dilute solution. The droplets can then be coalesced by trapping them and recovering the concentrated protein in the new liquid phase. Typically, in such a droplet fractionation process a collected enzyme can be degraded in its ability to catalyze a chemical reaction. In this article, we explore whether the initial solution pH control variable can be adjusted to minimize the decrease of enzyme activity in this process. The protein droplet recovery problem is one in which the recovered amount of desired protein (enzyme) in the droplet is maximized, subject to the minimization of the enzyme activity loss. The partition coefficient, which is the ratio between the protein concentration in the droplets and the residual solution, is maximized at approx 4.8 and occurs at pH 3.0. Here, the partition coefficient for invertase decreases as the initial solution pH increases, between pH 3.0 and 8.0. Interestingly, the initial solution surface tension seems to be inversely proportional to the partition coefficient. The partition coefficient reaches a maximum value at a surface tension value of approx 63 mN/m at pH 3.0. The enzymatic activity of the initial, the residual, and the droplet solutions all decrease as the bulk solution pH increases. A decrease of enzymatic activity was observed in the residual bulk solution when compared with that in the initial bulk solution at all pH levels. Also, up to 90% of the invertase activity was lost in the droplets when compared to the initial bulk solution.
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PMID:Partitioning invertase between a dilute water solution and generated droplets. 1530 18