• Korean Journal of Microbiology
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• v.16 no.3
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• pp.122-130
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• 1978

During the sporulation stage in Saccharomyces cerevisiae J170, the incorporation of $D^{14}$ C-glucose into starved cells of sporulation stage as well as the vegetative one is appeared higher at pH 6.0. Glucose transport system, in both the vegetative and sporulation stage, is associated with "energy dependent" as the result of repression by such a respiratory inhibitor as 2, 4-dinitrophenol. The Km value of glucose uptake in vegetative stage and sporulation stage was 2.1 mM and 2.5 mM respectively, indicating that the glucose is considerably reuqired for vegetative growth. Competition and countertranspoer of glucose by frutose and galactose are more distinct in vegetative stage, comparing with sporulation stage. The main sugar components of yeast cells consists of ribose, mannose, and ${\alpha}, \;{\beta}-glucose$. Amounts of mannose is lower in the aporulation stage than that in the vegetative stage.

• Korean Journal of Microbiology
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• v.9 no.1
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• pp.39-45
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• 1971

During the sporulation stage in Saccharomyces cerevisiae J170, the incorporation of D$^{14}$ C-glucose into starved cells of sporulation stage as well as the vegetative one is appeared higher at pH 6.0. Glucose transport system, in both the vegetative and sporulation stage, is associated with "energy dependent" as the result of repression by such a respiratory inhibitor as 2,4-dinitrophenol. The Km value of glucose uptake in vegetative stage and sporulation stage was 2.1 mM and 2.5 mM respectively, indicating that the glucose is considerably reuqired for vegetative growth. Competition and countertranspoer of glucose by frutose and galactose are more distinct in vegetative stage, comparing with sporulation stage. The main sugar components of yeast cells consists of ribose, mannose, and .apha., .betha.-glucose. Amounts of mannose is lower in the aporulation stage than that in the vegetative stage.ive stage.

• Journal of Nutrition and Health
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• v.36 no.8
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• pp.828-833
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• 2003

Dially disulfide (DADS), a component of garlic (Allium sativum), has been known to exert potent chemopreventive activity against various cancers. In this study, the synergistic effect of DADS and daunorubicin on the cytotoxicity of HL-60 cells, a human leukemia cell line, was investigated. DADS at 25 M greatly potentiated daunorubicin-induced cell death, decreasing cell viabilityto50%ofthe control. Daunorubicin-induced apoptosis was accompanied by the activation of caspase-3, the degradation of poly-(ADP-ribose) polymerase (PARP) and D4-GDI, and DNA fragmentation, which were blocked by pre-treatment with acetyl-Asp-Glu-Val-Asp- dialdehyde (Ac-DEVD-CHO). Treatment that combined 25 M DADS and 100 nM daunorubicin caused a similar degree of caspase-3 activation, PARP and D4-GDI degradation, and DNA fragmentation to that caused by treatment with 250 nM daunorubicin alone. These results indicate that combined therapy using daunorubicin with DADS, a component of food, and garlic can effectively decrease the therapeutic dose of daunorubicin, preventing the severe side effects of daunorubicin.

• Journal of Microbiology and Biotechnology
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• v.2 no.2
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• pp.78-84
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• 1992

Streptomyces sp. No.8, which produced glucose isomerase was isolated from soil samples. The isolated strain, No.8, was identified as belonging to the Genus Streptomyces. A mutant strain, SM 805, showed the greatest ability to produce glucose isomerase. It was developed from the strain, No.8, by mutagenesis induced by NTG and UV treatment. The mutant strain, SM 805, produced about 7 times more glucose isomerase than the parental strain, No.8. This enzyme catalyzed the isomerization of D-xylose, D-glucose and D-ribose. It was inactive in the absence of metal ions, but was activated by the addition of $Mg^{2+}$ or $Co^{2+}$. The optimum temperature and pH for enzyme activity were $80^\circ{C}$ and pH 8.5, respectively. The enzyme was stable in a pH range of 6.0 to 10.0, and it was highly thermostable. There was no activity loss below $80^\circ{C}$, and even above $90^\circ{C}$ about 45% of its activity was retained. The reaction equilibrium was reached when about 53% fructose was present in the reaction mixture. Whole cells containing glucose isomerase from Streptomyces sp. SM 805 were immobilized by glutaraldehyde treatment. The resultant immobilized enzyme pellets showed a relatively long stability during the isomerizing reaction. The half-life of the immobilized enzyme during the operating was 45 days in the presence of 10mM $Mg^{2+}$.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.122-127
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• 2001

This study was conducted to investigate the characteristics and biological activities of the substance extracted from the fruit body of Formitopsis rosea. The substance was extracted by hot water and then it was separated high and low molecular weight fraction by ethanol precipitation, The high molecular weight fraction was found to be a proteoglycan composed of glucose, mannose, galactose, xylose, fructose, ribose and amino acids. The amino acids of proteoglycan were mainly threonine, isoleucine, glycine, aspartic acid. Anticomplementary activity of the high molecular weight fraction was higher than that of the low molecular weight fraction. And also, the high molecular weight fraction enhanced phagocytic activity and nitric oxide production of macrophage. In enzymatic lipid peroxidation reaction with $ADP-FeCl_3-NADPH$, the lipid peroxidation was inhibited 82.4% and 86.6% by high and low molecular weight fractions, in nonenzymatic lipid peroxidation reaction, it was 83.0% and 84.6%, respectively.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.385-392
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• 1996

Bacillus stearotheymophilus, a potent xylanolytic bacterium isolated from soil, was tested for the strain's strategies of pentose utilization and the evidence of substrate preferences. The strain metabolized glucose, xylose, ribose, maltose, cellobiose, sucrose, arabinose and xylitol. The efficacy of the sugars as a carbon and energy source in this strain was of the order named above. The organism, however, could not grow on glycerol as a sole growth substrate. During cultivation on a mixture of glucose and xylose or arabinose, the major hydrolytic products of xylan, B. stearothermophilus displayed classical diauxic growth in which glucose was utilized during the first phase. On the other hand, the pentose utilization was prevented immediately upon addition of glucose. Cellobiose was preferred over xylose or arabinose. In contrast, maltose and pentose were co-utilized, and also no preference on between xylose and arabinose. Enzymatic studies indicated that B. stearothermophilus possessed constitutive hexokinase, a key enzyme of the glucose metabolic system. While, the production of $^{D}$-xylose isomerase, $^{D}$-xylulokinase and $^{D}$-arabinose isomerase essential for pentose phosphate pathway were induced by xylose, xylan, and xylitol but repressed by glucose. Taken together, the results suggested that the sequential utilization of B. stearothermophilus would be mediated by catabolite regulatory mechanisms such as catabolite inhibition or inducer exclusion.

• Macromolecular Research
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• v.12 no.4
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• pp.359-366
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• 2004

The polysaccharide, (1\longrightarrow5)-$\alpha$-D-ribofuranan, was synthesized by a cationic ring-opening polymerization of 1,4-anhydro-2,3-di-O-benzyl-$\alpha$-D-ribopyranose with the aid of boron trifluoride etherate and subsequent debenzylation. This polysaccharide catalyzed the hydrolysis of ethyl p-nitrophenyl phosphate, uridylyl(3'\longrightarrow5')uridine ammonium salt, and 4-tert-butylcatechol cyclic phosphate N-methyl pyridinium. The polymer also catalyzed the cleavage of nucleic acids (DNA and RNA). The hydrolysis of ethyl p-nitrophenyl phosphate in the presence of the polymer was accelerated by 1.5 ${\times}$ 10$^3$ times relative to the uncatalyzed reaction. The catalytic activity was attributable to the vic-cis-diols of the riboses being located inside the active center that is formed by polymer chain folding; these diols form hydrogen bonds with two phosphoryl oxygen atoms of the phosphates so as to activate the phosphorus atoms to be attacked by nucleophile ($H_2O$).

• Korean Journal of Microbiology
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• v.16 no.2
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• pp.47-61
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• 1978

Strptomyces albus T-12 which ahd been isolated and identified in the laboratory, was selected for the studies on the cultural conditions on the production of D-xylose iosmerase and the enzymological characteristics using the partially purified enzyme. The best results in the enzyme production came from D-xylose medium than wheat bran. The divalent metla ions as $Co^{2+},\;Fe^{2+},\;Zn^{2+}\;and\;Cu^{2+}$ retard or inhibit the cell-growth at the early stages of mycelia propagations, and T-12 strain is especially sensitive to $Co^{2+}$. After 60 hours of shaking cultivation at $30^{\circ}C$ and 200 rpm, a maximum enzyme activitz, 0.49 enzyme units, was obtained. Cell-free enzyme obtained from mycelia heat-treated in the prescence of 0.5mM $Co^{2+}$, showed a 2.4-fold increase in specific than the enzyme from untreated mycelia. The specific activity of the purified enzyme through Sephadex G-150 columm showed 180 fold to the crude enzyme. The effective activators of the enzyme appeared to be $Mg^{2+}\;and\;Co^{2+}$ ions, and it exhibited the maximal enzyme activity showed at pH 7.0 and at tempersture around $80^{\circ}C$ when $Mg^{2+}\;and\;Co^{2+}$ ions were added. The enzyme isomerized D-glucose, D-xylose, D-ribose, L-arabinose, D-mannose, and L-rhamnose in the present of $Mg^{2+}\;and\;Co^{2+}$ ions as an activatiors. $Mg^{2+}\;and\;Co^{2+}$ ions were non-competitively bound at different allosterix sites of enzyme molecule. $Mg^{2+}(5mM)\;or\;Co^{2+}(1.0mM)$ protected against the thermal denaturations of the enzyme activities. The michelis constant(Km) and $V_{max}$ values of the emzyme for D-glucose and D-xylose were 0.52M, $2.12{\mu}moles/ml{\cdot}min.\;and\;0.28M,\;0.65moles/ml{\cdot}min.$, respectively.

• Korean Journal of Agricultural Science
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• v.34 no.2
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• pp.99-109
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• 2007

Cellulomanas sp. CS 1-1 was studied for its morphological, physiological and biochemical characteristics, together with DNA homology and fatty acid pattern to elucidate its taxonomical position in the species level. Colony morphology of CS1-1 exhibited circular form, opaque, convex, entire edge and pale yellow. Cells were of rod with the size of $0.3{\sim}0.5{\times}0.8{\sim}1.2{\mu}m$, while coryneforms were formed at the early stage of culture. D-ribose, raffinose, rhamnose, acetate, propionate, L-lactate, D-gluconate, aspartate and proline were not utilized as a sole source of carbon, whereas saccharose, arabinose, and amlyose were utilized. Biochemical characteristics of CS1-1 were Gram positive, catalase positive, oxidase negative, nonmotile, facultative anaerobic, mesophilic and G+C content of 74.7 mol %. The major fatty acid and menaquinone were 12-methyltetradecanoic acid(anteiso-$C_{15:1}$) and MK-$9(H_4)$, respectively. These results were correspondent with the characteristics reported for member of the genus Cellulomonas. The strain CS 1-1 exhibited a high level of DNA homology as 70% with C. uda ATCC491, compared to those of 54~59% with C. fimi ATCC 15724, 46~48% with C. biazotea, C. gelida and C. bibula. Finally, strain CS1-1 could be classified as a novel species belongs to C. uda.

• Journal of Life Science
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• v.10 no.1
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• pp.20-23
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• 2000

Mono-ADP-ribosylation, catalyzed by ADP-ribosyltransferases, is a post-translational modification of proteins in which the ADP-ribose moiety of NAD is transferred to an acceptor protein. Previously, we have identified and cloned a glycosylphosphatidylinositol-linked ADP-ribosyltransferase (Yac-1) from mouse lymphoma cells. Yac-1 enzyme contains three regions (region I,II,III) similar to those found in several bacterial toxins and vertebrate ADP-ribosyltransferases. Site-directed mutagenesis was performed to verify the role of Glu 233 in region III. Mutants E233Q, E233D and E233A were inactive for ADP-ribosyltransferase activity. Thus Glu 233 in Yac-1 is essential for enzyme activity, suggesting that Glu 233 in Glu-rich motif near the carboxy terminus plays a catalytic role in ADP-ribosyltransferase activity.