PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GLUCOSE OXIDASE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

Expression of the Aspergillus niger glucose oxidase gene in Saccharomyces cerevisiae and its potential applications in wine production.

There is a growing consumer demand for wines containing lower levels of alcohol and chemical preservatives. The objectives of this study were to express the Aspergillus niger gene encoding a glucose oxidase (GOX; beta- d-glucose:oxygen oxidoreductase, EC 1.1.3.4) in Saccharomyces cerevisiae and to evaluate the transformants for lower alcohol production and inhibition of wine spoilage organisms, such as acetic acid bacteria and lactic acid bacteria, during fermentation. The A. niger structural glucose oxidase (gox) gene was cloned into an integration vector (YIp5) containing the yeast mating pheromone alpha-factor secretion signal (MFalpha1(S)) and the phosphoglycerate-kinase-1 gene promoter (PGK1(P)) and terminator (PGK1(T)). The PGK1(P)- MFalpha1(S)- gox- PGK1(T) cassette (designated GOX1) was introduced into a laboratory strain (Sigma1278) of S. cerevisiae. Yeast transformants were analysed for the production of biologically active glucose oxidase on selective agar plates and in liquid assays. The results indicated that the recombinant glucose oxidase was active and was produced beginning early in the exponential growth phase, leading to a stable level in the stationary phase. The yeast transformants also displayed antimicrobial activity in a plate assay against lactic acid bacteria and acetic acid bacteria. This might be explained by the fact that a final product of the GOX enzymatic reaction is hydrogen peroxide, a known antimicrobial agent. Microvinification with the laboratory yeast transformants resulted in wines containing 1.8-2.0% less alcohol. This was probably due to the production of d-glucono-delta-lactone and gluconic acid from glucose by GOX. These results pave the way for the development of wine yeast starter culture strains for the production of wine with reduced levels of chemical preservatives and alcohol.

Aspergillus niger↗

Glucose oxidase from Aspergillus niger. Cloning, gene sequence, secretion from Saccharomyces cerevisiae and kinetic analysis of a yeast-derived enzyme.

The gene for Aspergillus niger glucose oxidase (EC 1.1.3.4) has been cloned from both cDNA and genomic libraries using oligonucleotide probes derived from the amino acid sequences of peptide fragments of the enzyme. The mature enzyme consists of 583 amino acids and is preceded by a 22-amino acid presequence. No intervening sequences are found within the coding region. The enzyme contains 3 cysteine residues and 8 potential sites for N-linked glycosylation. The protein shows 26% identity with alcohol oxidase of Hansenuela polymorpha, and the N terminus has a sequence homologous with the AMP-binding region of other flavoenzymes such as p-hydroxybenzoate hydroxylase and glutathione reductase. Recombinant yeast expression plasmids have been constructed containing a hybrid yeast alcohol dehydrogenase II-glyceraldehyde-3-phosphate dehydrogenase promoter, either the yeast alpha-factor pheromone leader or the glucose oxidase presequence, and the mature glucose oxidase coding sequence. When transformed into yeast, these plasmids direct the synthesis and secretion of between 75 and 400 micrograms/ml of active glucose oxidase. Analysis of the yeast-derived enzymes shows that they are of comparable specific activity and have more extensive N-linked glycosylation than the A. niger protein.

Amino Acid Sequence↗

[Selection of Penicillium funiculosum strains with high glucose oxidase activity].

Metabolic inhibitors, riboflavin, and end products of glucose oxidation were shown to hold much promise for the selection of Penicillium funiculosum mutant strains with a high glucose oxidase activity. The incidence of positive mutations was highest in clones resistant to sodium azide, riboflavin, and beta-D-glucono-delta-lactone. Enzyme activity in Penicillium funiculosum mutants was studied under conditions of submerged cultivation. The intensity of glucose oxidase synthesis in seven cultures was 24-56% higher than that in the parent strain of Penicillium funiculosum NMM95.132.

Drug Resistance, Microbial↗

An amperometric glucose-oxidase/poly(o-phenylenediamine) biosensor for monitoring brain extracellular glucose: in vivo characterisation in the striatum of freely-moving rats.

Amperometric glucose biosensors based on the immobilization of glucose oxidase (GOx) on Pt electrodes with electropolymerized o-phenylenediamine (PPD) were implanted in the right striatum of freely-moving rats. Carbon paste electrodes for the simultaneous monitoring of ascorbic acid (AA) and/or tissue O2 were implanted in the left striatum. A detailed in vivo characterization of the Pt/PPD/GOx signal was carried out using various pharmacological manipulations. Confirmation that the biosensor responded to changing glucose levels in brain extracellular fluid (ECF) was obtained by intraperitoneal (i.p.) injection of insulin that caused a decrease in the Pt/PPD/GOx current, and local administration of glucose (1 mM) via an adjacent microdialysis probe that resulted in an increase in the biosensor current. An insulin induced increase in tissue O2 in the brain was also observed. Interference studies involved administering AA and subanaesthetic doses of ketamine i.p. Both resulted in increased extracellular AA levels with ketamine also causing an increase in O2. No significant change in the Pt/PPD/GOx current was observed in either case indicating that changes in O2 and AA, the principal endogenous interferents, have minimal effect on the response of these first generation biosensors. Stability tests over a successive 5-day period revealed no significant change in sensitivity. These in vivo results suggest reliable glucose monitoring in brain ECF.

Animals↗

Effects of interleukin 4 on production of IgE monoclonal antibodies directed against glucose oxidase.

Interleukin 4 is a cytokine that promotes the growth of B cells and the synthesis of IgE subclass antibody. Here we report the results of our study that was designed to determine if recombinant murine interleukin 4 (rmIL-4) can increase the yield of hybridomas secreting IgE subclass monoclonal antibodies directed against glucose oxidase. Three BALB/c mice (test group) were primed i.p. with 50 micrograms of glucose oxidase and then boosted i.v. 2 weeks later with 5 micrograms of glucose oxidase plus 200 ng of rmIL-4. A standard hybridoma fusion was performed 3 days later, and the fusion products were then cultured in the presence of 20 ng of rmIL-4 per milliliter. Another group of three mice underwent an identical immunization and fusion procedure, except that the rmIL-4 was omitted (control group). At 21 days after fusion, the test group had a significantly greater frequency of wells with hybridomas (average frequency = 191 per 1000 wells in test group versus 58 in control group; chi 2 = 1803; p = 0.0001) and wells containing IgG anti-glucose oxidase (mean of 23 per 1000 wells in test group versus 3 in control group; chi 2 = 506, p = 0.0001). Moreover, the IL-4-treated group had a significantly higher frequency of wells containing IgE antibodies (mean of 44 versus 11 in control group; chi 2 = 288, p = 0.0001) and IgE antibodies directed against glucose oxidase (mean of 5 per 1000 wells versus 2 in control group; chi 2 = 21, p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Glucose oxidase synthesis by Aspergillus niger GIV-10 on starch.

The effect of various kinds of starch, as the sole source of organic carbon, on the biosynthesis of glucose oxidase by A. niger GIV-10 was examined. A. niger grown on 6% wheat starch medium provided extracellular and intracellular glucose oxidase with the highest enzymatic activities. A new method of intracellular glucose oxidase extraction (without disruption of mycelium), developed and discussed in this paper, increased 2 to 3.8-times glucose oxidase yield, as compared to that described earlier.

Aspergillus niger↗

Simultaneous production of catalase, glucose oxidase and gluconic acid by Aspergillus niger mutant.

The production of gluconic acid, extracellular glucose oxidase and catalase in submerged culture by a number of biochemical mutants has been evaluated. Optimization of stirrer speed, time cultivation and buffering action of some chemicals on glucose oxidase, catalase and gluconic acid production by the most active mutant, AM-11, grown in a 3-L glass bioreactor was investigated. Three hundred rpm appeared to be optimum to ensure good growth and best glucose oxidase production, but gluconic acid or catalase activity obtained maximal value at 500 or 900 rpm, respectively. Significant increase of dissolved oxygen concentration in culture (16-21%) and extracellular catalase activity were obtained when the traditional aeration was employed together with automatic dosed hydrogen peroxide.

Aspergillus niger↗

Synthesis of glucose oxidase and catalase by Aspergillus niger in resting cell culture system.

The synthesis of glucose oxidase and catalase by Aspergillus niger was investigated using a resting cell culture system without growth being established. Calcium carbonate induced the synthesis of both enzymes and calcium chloride inhibited it. The optimal pH for the biosynthesis of glucose oxidase and catalase was 6.0 and 5.7, respectively. The effects of other bivalent cations, reductive compounds and metabolic products on enzyme synthesis were also tested. The biosynthesis of glucose oxidase and catalase was promoted by MnCO3, thioglycolic acid, pyroracemic acid and gluconic acid.

Aspergillus niger↗

Alginate/carbon composite beads for laccase and glucose oxidase encapsulation: application in biofuel cell technology.

Alginate-carbon beads were prepared in order to develop a biocompatible matrix for laccase and glucose oxidase immobilization for application in biofuel cell technology. The enzyme loading capacity was high (91%) in pure alginate beads for glucose oxidase. For laccase, the loading capacity was enhanced from 75% to 83% by introducing carbon. Desorption out of the matrix was controlled by the enzymes' diffusion and reached a plateau after 40 h for laccase and 70 h for glucose oxidase. Two-thirds of both enzymes was irreversibly retained inside the alginate beads. This proportion increased to 80% for laccase in combined alginate/carbon beads. Half-life of the adsorbed enzyme was enhanced to 74 days for laccase in carbon/alginate beads and 45 days for glucose oxidase in pure alginate as compared to 38 days and 23 days for free enzymes, respectively.

Adsorption↗

Effect of deglycosylation of N-linked sugar chains on glucose oxidase from Aspergillus niger.

Endo-beta-N-acetylglucosaminidase from Flavobacterium sp. released about 30% of the N-linked sugar chains from the glucose oxidase of Aspergillus niger. To elucidate the role of the carbohydrate moiety, the enzymatic properties of native and carbohydrate-depleted glucose oxidases were compared. It was found that their catalytic activities and thermal and pH stabilities were identical. However, the carbohydrate-depleted glucose oxidase was more rapidly precipitated by the addition of trichloroacetic acid and ammonium sulfate than the native enzyme. These results show that the N-linked sugar chains of the glucose oxidase contributed to the high solubility of the enzyme in water.

Acetylglucosaminidase↗

A discussion of anti-Aspergillus niger glucose oxidase monoclonal antibody reactivity to red blood cells of several species.

We observed that mouse spleen cells from rosettes with autologous red blood cells (RBCs) and that rosette-formation was suppressed by anti-Aspergillus niger glucose oxidase monoclonal antibody (mAb). In the present study, we investigated whether RBCs of species besides mice have the structure recognized by anti-A. niger glucose oxidase mAb by using rosette-formation and complement-mediated hemolysis. Lysates of monkey and human RBCs did not suppress rosette-formation whereas autologous (mouse), rat and sheep RBC lysates partially suppressed rosette-formation. Those lysates exerted their suppressive activity after they had been treated at 56 degrees C for 30 min. A. niger glucose oxidase also suppressed rosette-formation with or without treatment at 56 degrees C for 30 min. Alternatively, anti-A. niger glucose oxidase mAb lysed mouse, rat and sheep RBCs but not human RBCs with complement. These findings suggest that the cell surfaces of mouse, rat and sheep RBCs have a structure which can be recognized by anti-A. niger glucose oxidase mAb while the cell surfaces of monkey and human RBCs do not.

Animals↗

Dynamic organization of mixed Langmuir films of glucose oxidase and stearylamine at the air-water interface.

The structure and the dynamic organization of a mixed Langmuir film of glucose oxidase and stearylamine at the air-water interface have been studied. The film has been first characterized at the air-water interface by surface pressure/area isotherms. The dynamics of the mixed film was studied by following the evolution of the film area at a constant pressure and the evolution of the pressure at a constant area. After transfer of the films on solid substrates, the chemical composition of the mixed film has been quantified by UV-vis and IR spectroscopies. These characterizations were carried out in order to study the incorporation of glucose oxidase into the stearylamine film, and its influence on the structural evolution of the film. From these results, the dynamic organization of this mixed film may be described. For short times, glucose oxidase molecules interact with stearylamine molecules in solution or at the interface; these interactions would lead to the formation of a complex between stearylamine and glucose oxidase molecules. For long times (at least 3 h), a homogeneous mixed film constituted essentially of this complex is obtained at the air-water interface. A detailed analysis by atomic force microscopy allowed us to support this model and the existence of the glucose oxidase/stearylamine complex.

Air↗

Use of avidin-biotin-glucose oxidase complex to detect antimalarial antibody in serum by light microscopy.

An immunohistochemical assay was developed combining an avidin-biotin-glucose oxidase complex procedure (ABC-GO) with light microscopy to detect specific antibody against Plasmodium falciparum. Thin blood films were prepared from culture material of P. falciparum and fixed with acetone. Antibody was detected by successive incubations with test serum, biotinylated goat antihuman antibody, avidin-biotin-glucose oxidase complex, and glucose oxidase substrate. In the presence of reactive serum, a blue precipitate formed on the parasites and could be visually observed with a 40x objective. Sera from patients with single infections for P. vivax or P. ovale were unreactive. No cross-reactivity was observed with sera from patients with rheumatoid arthritis, filariasis, amebiasis, schistosomiasis, dengue, scrub typhus, leptospirosis, or toxoplasmosis. The sensitivity of ABC-GO is comparable to that of the indirect fluorescent antibody test.

Animals↗

The incidence and immediate respiratory consequences of pulmonary aspiration of enteral feed as detected using a modified glucose oxidase test.

Pulmonary micro-aspiration of enteral feed in intubated critically ill patients has been reported to occur commonly. In this prospective observational study the incidence of micro-aspiration, diagnosed by a modified glucose oxidase test, is reported in 25 enterally fed critically ill and tracheally intubated patients on a general intensive care unit. Episodes of microaspiration were correlated with changes in PaO2/FiO2 ratio as an index of changes in degree of lung injury. The modified glucose oxidase test differs from the traditional glucose oxidase test because of the enrichment of the feed with glucose (10 g glucose added to 500 ml enteral feed resulting in a tenfold increase in glucose concentration). Pulmonary aspiration of feed was detected by exposing a glucose oxidase strip to tracheal secretions. The feed was enriched with glucose to improve the ability of the reagent strip to detect the feed. The incidence of aspiration of feed was 44% with a prevalence of 6.9% per day of intubation. Only 43% of these episodes of aspiration were detected by the feed being seen in the tracheal secretions. Aspiration was associated with a mean fall in the PaO2/FiO2 ratio of 5.6 kPa from 27.1 kPa to 21.5 kPa (P = 0.002). Aspiration of enteral feed is common and causes a demonstrable morbidity. Detection using this simple bedside test may alert the clinician to institute measures to minimize further aspiration.

Enteral Nutrition↗

Resonance coherent anti-Stokes Raman scattering spectra of fluorescent biological chromophores: Vibrational evidence for hydrogen bonding of flavin to glucose oxidase and for rapid solvent exchange.

Coherent anti-Stokes Raman scattering (CARS) spectra are reported for flavin adenine dinucleotide (FAD) and glucose oxidase (beta-D-glucose:oxygen 1-oxidoreductase; EC 1.1.3.4), in resonance with the 450 nm flavin absorption band. Several isoalloxazine ring modes were observed (1635, 1584, 1507, 1416, and 1359 cm(-1)). A 12 cm(-1) increase in one component of the 1359 cm(-1) band upon binding to glucose oxidase was attributed to hydrogen bonding of the N3 proton to a protein acceptor. This interpretation is consistent with deuteration results. Smaller decreases (5-7 cm(-1)) on binding were observed for the 1635 and 1416 cm(-1) modes (and also a 1297 cm(-1) mode of deuterated FAD) and were attributed to environmental effects. Deuteration of bound FAD was observed within 5 min of mixing glucose oxidase with D(2)O, demonstrating ready access to solvent. Lorentzian CARS peaks were observed with omega(as) at the peak of the 450 nm absorption band, a condition which corresponds to maximum resonance enhancement if the peak corresponds to the envelope of 0-1 vibronic transitions. If omega(1) was tuned to the peak, then dispersion lineshapes were observed, reflecting a loss of Raman enhancement relative to the electronic background.

Journal Article↗

A sulfonamide based glucose-responsive hydrogel with covalently immobilized glucose oxidase and catalase.

A new glucose-sensitive hydrogel, based on sulfonamide chemistry with covalently conjugated glucose oxidase and catalase, was synthesized and tested. The pH-induced full swelling transition of the gel occurred in the range of pH 6.5 approximately 7.5. In a glucose concentration range of 0-300 mg/dl in an isotonic phosphate buffered saline solution (pH 7.4), the pH inside the gel varied from pH 7.4 to 7.2. At the same glucose concentration range, the gel showed reversible glucose dependent swelling without hysteresis from 12 to 8, expressed in water (g)/polymer (g).

Catalase↗

Improved operational stability of peroxidases by coimmobilization with glucose oxidase.

The operational stability of peroxidases was considerably enhanced by generating hydrogen peroxide in situ from glucose and oxygen. For example, the total turnover number of microperoxidase-11 in the oxidation of thioanisole was increased sevenfold compared with that obtained with continuous addition of H(2)O(2). Coimmobilization of peroxidases with glucose oxidase into polyurethane foams afforded heterogeneous biocatalysts in which the hydrogen peroxide is formed inside the polymeric matrix from glucose and oxygen. The total turnover number of chloroperoxidase in the oxidation of thioanisole and cis-2-heptene was increased to new maxima of 250. 10(3) and 10. 10(3), respectively, upon coimmobilization with glucose oxidase. Soybean peroxidase, which normally shows only classical peroxidase activity, was transformed into an oxygen-transfer catalyst when coimmobilized with glucose oxidase. The combination catalyst mediated the enantioselective oxidation of thioanisole [50% ee (S)] with 210 catalyst turnovers.

Chloride Peroxidase↗

Application of immobilized enzymes to clinical analyses : use of co-immobilized glucose oxidase and peroxidase in column form.

Glucose oxidase from Aspergillus niger and peroxidase from horseradish were simultaneously immobilized onto alkylamine glass beads which were then packed into a 1.5 x 20 mm column and integrated in the flow system of an AutoAnalyzer I. Glucose in serum, up to 5.0 g/l, was continuously determined at a rate of 60 samples per hour. The co-immobilized enzyme column gave better sensitivity as compared with an enzyme column which contained a mixture of two kinds of individually immobilized enzymes. The enzyme column was sufficiently stable while in use for two months. The results correlated satisfactorily well with those obtained by other well established methods for glucose assay.

Blood Glucose↗