• BMB Reports
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• v.38 no.5
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• pp.609-618
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• 2005

$\gamma$-Glutamyl transpeptidase (GGT, EC 2.3.2.2.) catalyzes the transfer of the $\gamma$-glutamyl moiety from $\gamma$-glutamyl containing ompounds, notably glutathione (GSH), to acceptor amino acids and peptides. A second gene (GGTII) encoding GGT was previously isolated and characterized from the fission yeast Schizosaccharomyces pombe. In the present work, the GGTII-lacZ fusion gene was constructed and used to study the transcriptional regulation of the S. pombe GGTII gene. The synthesis of $\beta$-galactosidase from the GGTII-lacZ fusion gene was significantly enhanced by NO-generating SNP and hydrogen peroxide in the wild type yeast cells. The GGTII mRNA level was increased in the wild-type S. pombe cells treated with SNP. However, the induction by SNP was abolished in the Pap1-negative S. pombe cells, implying that the induction by SNP of GGTII is mediated by Pap1. Fermentable carbon sources, such as glucose (at low concentrations), lactose and sucrose, as a sole carbon source, enhanced the synthesis of $\beta$-galactosidase from the GGTII-lacZ fusion gene in wild type KP1 cells but not in Pap1-negative cells. Glycerol, a non-fermentable carbon source, was also able to induce the synthesis of $\beta$-galactosidase from the fusion gene, but other non-fermentable carbon sources such as acetate and ethanol were not. Transcriptional induction of the GGTII gene by fermentable carbon sources was also confirmed by increased GGTII mRNA levels in the yeast cells grown with them. Nitrogen starvation was also able to induce the synthesis of $\beta$-galactosidase from the GGTII-lacZ fusion gene in a Pap1-dependent manner. On the basis of the results, it is concluded that the S. pombe GGTII gene is regulated by oxidative and metabolic stress.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.685-692
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• 2001

A gene, Egl, from Paenibacillus sp. KCTC 8848P encoding endo-${\circ}$-1,4-glucanase was cloned and expressed in Escherichia coli. It consisted of an open reading frame of 1,191 bp for a protein that consisted of 397 amino acids with a molecular weight of 44,539 Da. The deduced amino acid sequence of the endo-${\circ}$-1,4-glucanase gene had a 94% similarity to the endo-$\beta$-1,4-glucanase of Bacillus polymyxa. The Egl gene was also expressed in Saccharomyces cerevisiae secreting Endomyces fibuliger $\beta$-glucosidase (BGL1) under the control of the alcohol dehydrogenase (ADC1) gene promoter, S. cerevisiae transformant producing both endo-${\circ}$-1,4-glucanase and ${\circ}$-glucosidase grew on carboxymethyl cellulose as the sole carbon source.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.946-950
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• 2014

Bacillus licheniformis was grown in minimal nutrient medium containing 1% (w/v) of distillers dried grain with soluble (DDGS), palm kernel meal (PKM), wheat bran (WB) or copra meal (CM), and the enzyme activity of endoglucanase, ${\beta}$-glucosidase, xylanase and reducing sugars was measured to investigate a possibility of using cost-effective agricultural residues in producing cellulolytic and hemicellulolytic enzymes. The CM gave the highest endoglucanase activity of 0.68 units/mL among added substrates at 48 h. CM yielded the highest titres of 0.58 units/ml of ${\beta}$-glucosidase, compared to 0.33, 0.23, and 0.16 units/mL by PKM, WB, and DDGS, respectively, at 72 h. Xylanase production was the highest (0.34 units/mL) when CM was added. The supernatant from fermentation of CM had the highest reducing sugars than other additional substrates at all intervals (0.10, 0.12, 0.10, and 0.11 mg/mL respectively). It is concluded that Bacillus licheniformis is capable of producing multiple cellulo- and hemicellololytic enzymes for bioethanol production using cost-effective agricultural residues, especially CM, as a sole nutrient source.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.597-605
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• 2018

Acyl-CoA oxidases (ACOXs) play important roles in lipid metabolism, including peroxisomal fatty acid ${\beta}$-oxidation by the conversion of acyl-CoAs to 2-trans-enoyl-CoAs. The yeast Yarrowia lipolytica can utilize fatty acids as a carbon source and thus has extensive biotechnological applications. The crystal structure of ACOX3 from Y. lipolytica (YlACOX3) was determined at a resolution of $2.5{\AA}$. It contained two molecules per asymmetric unit, and the monomeric structure was folded into four domains; $N{\alpha}$, $N{\beta}$, $C{\alpha}1$, and $C{\alpha}2$ domains. The cofactor flavin adenine dinucleotide was bound in the dimer interface. The substrate-binding pocket was located near the cofactor, and formed at the interface between the $N{\alpha}$, $N{\beta}$, and $C{\alpha}1$ domains. Comparisons with other ACOX structures provided structural insights into how YlACOX has a substrate preference for short-chain acyl-CoA. In addition, the structure of YlACOX3 was compared with those of medium- and long-chain ACOXs, and the structural basis for their differences in substrate specificity was discussed.

• Natural Product Sciences
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• v.15 no.1
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• pp.44-49
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• 2009

Seven monoterpenes, three sesquiterpenes, three phenolics and one flavonoid were isolated from the MeOH extract of Amomum xanthioides. Their structures were determined by spectroscopic methods to be caryophyllene oxide (1), bornyl acetate (2), nerolidol (3), spathulenol (4), (-)-borneol (5), (+)-5-endohydroxycamphor (6), vanillic acid (7), protocatechuic acid methyl ester (8), betulabuside A (9), (1R,4S,6R)-6-hydroxyfenchan-2-one-6-O-$\beta$-D-glucopyranoside (10), (1S,4R,6S)-6-hydroxybornan-2-one-6-O-$\beta$-D-glucopyranoside (11), (1R,2S,4S,5R)-angelicoidenol 2-O-$\beta$-D-glucopyranoside (12), 1-O-vanilloyl-$\beta$-D-glucopyranoside (13), and quercetin-3-rhamnopyranoside (14). Compounds 6-14 were isolated for the first time from this plant source. Compounds 3 and 4 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.153-157
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• 1999

The effececl of levanoclaose produced by levanase Croni Pseuc/olol~~o!!n.s sp. K-52 on pnnciple inlesimal microflorawas investigated. The reaction product, levanoctaose, was used as a carbon source for various intestinalmicroflora. Especially. Bijidobacteriulolr~ adolescentis and Lnctohaciilrrs ocidophilus grew effectively in vitroexpeiiments, whereas Clostridiunz per.frilol~gerzs, Bactetvid,~ngilis, Eschericlzin. coli, and Stnplzylococcus nureirsdid not. Therefore, levanoctdose seemed to proinole selectively the growth ol" B. ndo1escenti.r and L. acidol~hi-/us. In Lhe in viva experiments, the effects of levanoctaose on inlestinal nucroflora were examined on heirgrowth. $\beta$-fri~ctosidase acliviiy. and butyrate concenuation in rats. Appuently, die number of fecal Bifidobacteria.the amount of bulyrate, and $\beta$-hctosidase activity were increased, whereas total aerobes 'and pH werereduced in rals Eed leviu~octaose diets, cornpxed with hose of the control diets. We concluded hat those effecismay be beneficial in improving gastrointestinal health.astrointestinal health.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.163-163
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• 2008

Methylophaga aminisulfidivorans $MP^T$, a restricted facultative marine methylotrophic bacterium, was able to utilize methanol as a sole carbon and energy source, and possessed a methanol dehydrogenase (MDH) that is a key enzyme in the process of methanol oxidation. During purification of MDH, three types of MDH (MDH I, II, and III) were obtained in the cell free extracts from $MP^T$ cells grown on methanol. When analyzed by SDS-PAGE and ESI-FT ICR MS, MDH I was confirmed to consist of two subunits and with molecular masses of ~66 and ~10 kDa, respectively, in a form of ${\alpha}_2{\beta}_2$. While MDH II and MDH III contained an additional ~30 kDa protein, designated ${\gamma}$, in a form of ${\alpha}_2{\beta}_2{\gamma}$ and ${\alpha}_2{\beta}_2{\gamma}_2$, respectively. MDH III showed 1.5.2.0 times higher activity than MDH II, while MDH I remained the lowest activity. Based on these observations and experimental data, it seems that the original MDH conformation is ${\alpha}_2{\beta}_2{\gamma}2$ within $MP^T$ growing on methanol, and subunit ${\gamma}$ keeps MDH in an active form, and/or makes MDH easily bind to the substrate, methanol.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.678-682
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• 2005

The promoter region of a carbon starvation gene isolated from Pseudomonas putida was cloned and analyzed for its potential use for in situ bioremediation and bioprocessing. We constructed a recombinant plasmid pMKD101 by cloning the 0.65 kb promoter region of the gene into the promoter proving vector, pMK301, which contains the lacZ for ${\beta}$-galactosidase activity as a reporter gene. pMKD101 was transformed into the wild-type P. putida MK1, resulting in P. putida RPD101, and analyzed for ${\beta}$-galactosidase activity under different culture conditions. When RPD101 was grown on the minimal medium plus $0.1\%$ glucose as a sole carbon source in batch cultures, ${\beta}$-galactosidase activity was found to be 3.2-fold higher during the stationary phase than during the exponential phase. In chemostat cultures, ${\beta}$-galactosidase activity was found to be 3.1-fold higher at the minimal growth rate (dilution rate=$0.05\;h^{-1}$) than at the maximal growth rate (dilution rate=$0.173;h^{-1}$). The results suggest that a carbon starvation promoter can be utilized to maximize the expression of a desired gene under nutrient limitation.

• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1120-1125
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• 2016

The neutron decay constant, ${\alpha}$, and effective delayed neutron fraction, ${\beta}_{eff}$, are important parameters for the control of the dynamic behavior of nuclear reactors. For the heavy water zero power reactor (HWZPR), this document describes the measurements of the neutron decay constant by noise analysis methods, including variance to mean (VTM) ratio and endogenous pulse source (EPS) methods. The measured ${\alpha}$ is successively used to determine the experimental value of the effective delayed neutron fraction as well. According to the experimental results, ${\beta}_{eff}$ of the HWZPR reactor under study is equal to 7.84e-3. This value is finally used to validate the calculation of the effective delayed neutron fraction by the Monte Carlo methods that are discussed in the document. Using the Monte Carlo N-Particle (MCNP)-4C code, a ${\beta}_{eff}$ value of 7.58e-3 was obtained for the reactor under study. Thus, the relative difference between the ${\beta}_{eff}$ values determined experimentally and by Monte Carlo methods was estimated to be < 4%.

• Korean Journal of Medicinal Crop Science
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• v.16 no.4
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• pp.231-237
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• 2008

This study was conducted to determine the amount of flavonoids in Salicomia herbacea L. grown by a liquid chromatography / mass spectrometry (LC/MS). The flavonoids-contained quercetin (124.43 ppm), rutin (2.57 ppm), quercetin-3-${\beta}$-glucoside (3992.49 ppm), quercetin-3',4'-glucoside (0.08 ppm) and isorhamnetin (27.81 ppm) were detected in the powder sample. In particular, quercetin-3-${\beta}$-glucoside accounted for more than 99% in hay and 96% in powder. These results suggest that S. herbacea, which is one of halophyte plants, has high functional substances as an antioxidant source.