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Containing Glucose (containing + glucose)
Kinds of Containing Glucose Selected AbstractsExistence of a tightly regulated water channel in Saccharomyces cerevisiaeFEBS JOURNAL, Issue 2 2001Valérie Meyrial The Saccharomyces cerevisiae strain ,1278b possesses two putative aquaporins, Aqy1-1p and Aqy2-1p. Previous work demonstrated that Aqy1-1p functions as a water channel in Xenopus oocyte. However, no function could be attributed to Aqy2-1p in this system. Specific antibodies were used to follow the expression of Aqy1-1p and Aqy2-1p in the yeast. Aqy1-1p was never detected whatever the growth phase and culture conditions tested. In contrast, Aqy2-1p was detected only during the exponential growth phase in rich medium containing glucose. Aqy2-1p expression was repressed by hyper-osmotic culture conditions. Both immunocytochemistry and biochemical subcellular fractionation demonstrated that Aqy2-1p is located on the endoplasmic reticulum (ER) as well as on the plasma membrane. In microsomal vesicles enriched in ER, a water channel activity due to Aqy2-1p was detected by stopped-flow analysis. Our results show that the expression of aquaporins is tightly controlled. The physiological relevance of aquaporin-mediated water transport in yeast is discussed. [source] Production of d -(,)-3-hydroxyalkanoic acid by recombinant Escherichia coliFEMS MICROBIOLOGY LETTERS, Issue 1 2003Kai Zhao Abstract Pathways for extracellular production of chiral d -(,)-3-hydroxybutyric acid (3HB) and d -(,)-3-hydroxyalkanoic acid (mcl-3HA) were constructed by co-expression of genes of ,-ketothiolase (phbA), acetoacetyl-CoA reductase (phbB) and 3-hydroxyacyl-ACP CoA transacylase (phaG), respectively, in Escherichia coli strain DH5,. The effect of acrylic acid and glucose on production of both 3HB and mcl-3HA was investigated. It was found that the addition of acrylic acid significantly increased production of 3HB and mcl-3HA consisting of 3-hydroxyoctanoic acid and 3-hydroxydecanoic acid in a ratio of 1:3 from 199 mg l,1 to 661 mg l,1 and from 27 mg l,1 to 135 mg l,1, respectively, in shake flask studies when glucose was present in the medium at the very beginning of fermentation. The timing of glucose addition had no effect on 3HB production. In contrast, mcl-3HA production was affected by glucose addition, an mcl-3HA concentration of 193 mg l,1 was obtained when glucose was added to the culture at 12 h. A more than seven-fold increase was obtained when compared with that in medium containing glucose at the beginning of fermentation. However, a decrease in production of 3HB and mcl-3HA was found when glucose was added at 12 h to the culture containing acrylic acid. The repressive effect of acrylic acid on acetic acid production was also evaluated and discussed. [source] Mycelium cultivation, chemical composition and antitumour activity of a Tolypocladium sp. fungus isolated from wild Cordyceps sinensisJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006P.H. Leung Abstract Aims:, To examine and illustrate the morphological characteristics and growth kinetics of Cs-HK1, a Tolypocladium fungus, isolated from wild Cordyceps sinensis in solid and liquid cultures, and the major chemical constituents and antitumour effects of Cs-HK1 mycelium. Methods and Results:, The Cs-HK1 fungus was isolated from the fruiting body of a wild C. sinensis and identified as a Tolypocladium sp. fungus. It grew rapidly at 22,25°C on a liquid medium containing glucose, yeast extract, peptone and major inorganic salts, with a specific growth rate of 1·1 day,1, reaching a cell density of 23·0 g dw l,1 in 7,9 days. Exopolysaccharides accumulated in the liquid culture to about 0·3 g l,1 glucose equivalent. In comparison with natural C. sinensis, the fungal mycelium had similar contents of protein (11·7,,g) and carbohydrate (654·6,,g) but much higher contents of polysaccharide (244·2 mg vs 129·5 mg), adenosine (1116·8,,g vs 264·6 ,g) and cordycepin (65·7 ,g vs 20·8 ,g) (per gram dry weight). Cyclosporin A, an antibiotic commonly produced by Tolypocladium sp., was also detected from the mycelium extract. The hot water extract of mycelium showed low cytotoxic effect on B16 melanoma cells in culture (about 25% inhibition) but significant antitumour effect in animal tests, causing 50% inhibition of B16 cell-induced tumour growth in mice. Conclusions:, The Tolypocladium sp. fungus, Cs-HK1, can be easily cultivated by liquid fermentation. The mycelium biomass contained the major bioactive compounds of C. sinensis, and the mycelium extract had significant antitumour activity. Significance and Impact of the Study:, The Cs-HK1 fungus may be a new and promising medicinal fungus and an effective and economical substitute of the wild C. sinensis for health care. [source] A cost effective fermentative production of succinic acid from cane molasses and corn steep liquor by Escherichia coliJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2006L. Agarwal Abstract Aim:, Development and optimization of an efficient and inexpensive medium for succinic acid production by Escherichia coli under anaerobic conditions. Methods and Results:, Initially, 0·8 gl,1 of succinic acid was produced in 60 h in 300-ml medium. On optimization, glucose and peptone were replaced by cane molasses and corn steep liquor. Three hundred ml of this medium was inoculated with 4% (v/v) of seed inoculum, incubated at 39°C for 72 h, resulted in 7·1 gl,1 of succinic acid in 36 h. Scale up in a 10-l fermentor under conditions of controlled pH and continuous CO2 supply in this medium resulted in 17 gl,1 of succinic acid in 30 h. Conclusions:, A ninefold increase in succinic acid production was obtained in 500-ml anaerobic bottles with optimized medium having cane molasses and corn steep liquor as against initial medium containing glucose and peptone. However, a subsequent scale up in a 10-l fermentor resulted in a 2·5-fold increase in succinic acid production as against optimized medium used in 500-ml anaerobic bottles. Significance and Impact of the Study:, Succinic acid production was enhanced in medium consisting of inexpensive carbon and nitrogen sources in a shorter span of time. [source] Lindane removal induction by Streptomyces sp.JOURNAL OF BASIC MICROBIOLOGY, Issue 5 2006Gamma-hexachlorocyclohexane (,-HCH or lindane), one of the most commonly used pesticides, has been mainly used in agriculture; this pesticide is known to be highly toxic and persistent, causing serious water and soil contamination. The objective of the present work is to study the effect of low glucose concentration and the addition of lindane at different growing time on the pesticide detoxification ability of Streptomyces M7. After 96 h of incubation in synthetic medium containing glucose 0.6 g l,1 with the addition of lindane 100 ,g l,1 at 20 h of incubation, a typical diauxic curve was obtained: glucose was the preferred substrate until 24 h, at 48 h, when the carbohydrate was depleted, the microorganism consumed the pesticide like carbon source. On the other hand, lindane removal induction was observed, which was greater when the pesticide was added to the medium at 20 h than 6 h of incubation. Between 72 and 96 h, a maximum of ,86% of the Cl, was released when lindane was added to the medium at 20 h, whereas ,70% and 67% Cl, was released in the medium when the pesticide was added at 0 and 6 h of incubation respectively. This is the first report of chloride release from inoculated medium supplemented with lindane, suggesting that the pesticide was degraded by Streptomyces sp. under aerobic conditions. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Interaction Between Potassium Sorbate and Aspartame in Aqueous Model Sugar SystemsJOURNAL OF FOOD SCIENCE, Issue 3 2001M.F. Gliemmo ABSTRACT: The interaction between potassium sorbate and aspartame in aqueous model sugar systems of 0.97 water activity and pH 3.0 was studied. Aspartame addition showed a protective effect over sorbate destruction in an aqueous system of approximately aw 1, as well as in a system containing glucose; but, in the presence of sucrose, it enhanced degradation. In all systems studied, addition of K sorbate and depression of water activity to 0.97 increased aspartame destruction. The combined use of K sorbate and aspartame exhibited strong nonenzymatic browning potential. The study demonstrated that nonenzynmatic browning can limit shelf life; and it is not recommended to use potassium sorbate together with aspartame. [source] Effects of Amylopectin/Amylose Starch Ratio on Growth, Body Composition and Glycemic Response of Sunshine Bass Morone chrysops × M. saxatilisJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2003Steven Rawles Manipulation of the ratio of amylopectin (,-[1,4] and ,-[1,6] linked glucose) to amylose (,-[1,41 linked glucose) starches in the carbohydrate fraction of the diet has been used to improve carbohydrate and lipid metabolism in mammalian models. A 10-wk feeding trial was conducted to determine the effect of dietary amylopectin/amylose ratio on growth and composition of growth of advanced sunshine bass (Morone chrysops × M. saxatilis) fingerlings (60 g, initial weight). Fish were fed cold-pelleted, semipurified, isonitrogenous (35% crude protein), isocaloric (3.6 kcaVg protein), isolipidic (5%) diets containing 25% carbohydrate. The carbohydrate fraction of the diets was composed of either glucose, dextrin, 100% amylopectin/0% amylose, 70% amylopectin/30% amylose, or 30% amylopectin/70% amylose. Diets differing in ratios of amylopectin/amylose were achieved by adjusting the proportion of high-amylopectin (100% amylopectin) to high-amylose (70% amylose) corn starch. Diets were fed to fish in quadruplicate 76-L tanks (seven fish/tank) connected to a brackish water (5-7%v) recirculating culture system with biofiltration. Weight gain ranged from 195 to 236% of initial weight (60 g) and was significantly greater (P < 0.1) for fish fed diets containing 25% carbohydrate as dextrin or as 70% amylose and significantly lower in fish fed diets in which carbohydrate was composed of 30% amylose, 100% amylopectin, or glucose. Feed efficiency ranged from 0.52 to 0.61 and was higher in fish fed the diet containing the highest concentration of amylose and lower in fish fed the diet containing glucose. Hepatosomatic index was highest (2.71) in fish fed the diet containing glucose and lowest (1.401.45) in fish fed diets containing high-amylose cornstarch. Intraperitoneal fat ratio was distinctly lower in fish fed diets containing some amylose as compared to those fed diets without amylose. Liver lipid was significantly lower (4.8%) in fish fed the diet containing glucose and almost twice as high (7.3-8.9%) in fish fed the diets containing any starch. Glycogen content of the liver decreased from approximately 12% in fish fed the diet containing glucose to 5% in fish fed the diets containing amylose. Muscle proximate composition and ratio were unaffected by the dietary treatments. Fasting levels (15 h) of blood glucose in fish reared for 10 wk on the diet containing glucose were significantly elevated (5.5 mmol/L) when compared to fasting levels of those that had been reared on diets containing starch (3.4-1.1 mmol/L). Fish fed the diet containing glucose exhibited maximum blood concentrations (14.6 mmoVL) 4 h postprandial then rapidly declined to nearly fasting levels within 8 h postprandial. In contrast, maximum plasma glucose concentrations in fish fed diets containing starch were roughly half (6.8-8.1 mmol/L) those of fish fed the diet containing glucose. Blood glucose in fish fed diets containing dextrin or predominantly amylopectin starch remained elevated longer than that of fish fed diets containing glucose or predominantly amylose starch. Glycemic response appeared to decrease with increasing dietary amylose content. These data suggest that feeding diets in which a greater portion of the starch is amylose may be a useful strategy for improving carbohydrate use in sunshine bass. [source] Characteristics of Saccharomyces cerevisiae gal1, and gal1,hxk2, mutants expressing recombinant proteins from the GAL promoterBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2005Hyun Ah Kang Abstract Galactose can be used not only as an inducer of the GAL promoters, but also as a carbon source by Saccharomyces cerevisiae, which makes recombinant fermentation processes that use GAL promoters complicated and expensive. To overcome this problem during the cultivation of the recombinant strain expressing human serum albumin (HSA) from the GAL10 promoter, a gal1, mutant strain was constructed and its induction kinetics investigated. As expected, the gal1, strain did not use galactose, and showed high levels of HSA expression, even at extremely low galactose concentrations (0.05,0.1 g/L). However, the gal1, strain produced much more ethanol, in a complex medium containing glucose, than the GAL1 strain. To improve the physiological properties of the gal1, mutant strain as a host for heterologous protein production, a null mutation of either MIG1 or HXK2 was introduced into the gal1, mutant strain, generating gal1,mig1, and gal1,hxk2, double strains. The gal1,hxk2, strain showed a decreased rate of ethanol synthesis, with an accelerated rate of ethanol consumption, compared to the gal1, strain, whereas the gal1,mig1, strain showed similar patterns to the gal1, strain. Furthermore, the gal1,hxk2, strain secreted much more recombinant proteins (HSA and HSA fusion proteins) than the other strains. The results suggest that the gal1,hxk2, strain would be useful for the large-scale production of heterologous proteins from the GAL10 promoter in S. cerevisiae. © 2005 Wiley Periodicals, Inc. [source] Hydrogen Production from Glucose by AnaerobesBIOTECHNOLOGY PROGRESS, Issue 6 2005Hiroyasu Ogino Various anaerobes were cultivated in media containing glucose. When 100 mL of thioglycollate medium containing 2.0% (w/v) glucose was used, Clostridium butyricum ATCC 859, NBRC 3315, and NBRC 13949 evolved 227,243 mL of biogas containing about 180 mL of hydrogen in 1 day. Although some strains had some resistance against oxygen, C. butyricum ATCC 859 and 860 did not have it. C.butyricum NBRC 3315 and Enterobacter aerogenes NBRC 13534 produced hydrogen in the presence of glucose or pyruvic acid, and E. aerogenes NBRC 13534 produced hydrogen by not only glucose and pyruvic acid but also dextrin, sucrose, maltose, galactose, fructose, mannose, and mannitol. When a medium containing 0.5% (w/v) yeast extract and 2.0% (w/v) glucose was used, E. aerogenes NBRC 13534 evolved more biogas and hydrogen than C. butyricum NBRC 3315 in the absence of reducing agent. [source] Comparison of PCR-DGGE and Selective Plating Methods for Monitoring the Dynamics of a Mixed Culture Population in Synthetic Brewery WastewaterBIOTECHNOLOGY PROGRESS, Issue 3 2005Kawai Tam Enrichment of an activated sludge inoculum in synthetic brewery wastewater, which included glucose, maltose, and ethanol, was conducted in batch experiments to identify the dominant microbes present, to determine methodologies capable of monitoring the mixed culture population dynamics, and to determine the consortiumapos;s substrate degradation behavior. These results and methodologies were subsequently used in the determination of the population dynamics of suspended and attached microorganisms in a sequencing batch system in the second part of this research work. The three-membered microbial community comprised two bacterial and one fungal species that were identified as Acinetobacter sp., Enterobacter sp., and Candida sp. PCR-DGGE and plating on selective media were used to track the population dynamics of the consortium during the degradation of different substrates in synthetic wastewater containing glucose, maltose, and ethanol. Enterobacter sp. could degrade glucose and maltose but not ethanol, whereas Acinetobacter and Candida could degrade all three carbon sources. In buffered batch mixed culture experiments, Enterobacter was the predominant bacterium until the sugar concentrations decreased to levels that enabled Acinetobacter and Candida to degrade ethanol. PCR-DGGE was effective for detecting the dominant species, but culture-based methods were more accurate for monitoring the population dynamics of these microorganisms during growth in the wastewater medium. [source] | |||||||||||||