• Korean Journal of Microbiology
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• v.38 no.4
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• pp.293-298
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• 2002

In order to investigate the ecological aspect of bacteria on groundwater, water samples were collected from various regions. Total of 318 strains were isolated from diluted nutrient broth (DNB) agar medium, and investigated their growth pattern on nutrient broth (NB) medium. As a result, all the isolated strains were divided into two groups, NB and DNB organisms. Growth of DNB organisms were suppressed in full strength NB medium but not in DNB medium, which were called oligotrophic bacteria in this study. Proportion of DNB organisms occurred in the frequency of 50-98% in potable groundwaters (CW, CJ, DPG, CJG1), however, it was 23,46% in polluted site (TJ, NPG1). One hundred and two strains were identified as oligotrophic bacteria and their phylogenetic characteristics were determined by using 16S rDNA sequencing. Based on the phylogenetic analysis, they were found to fall into three major phylogenetic groups: belonging to the Proteobacteria $\alpha$-(49 strains), $\beta$-(50 strains), $\gamma$ -(3 strains) subdivisions. The phylogenetic analysis suggested that microbial diversity of potable groundwater is more complex than that obtained in the past investigation.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.8-16
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• 2013

An agar-hydrolyzing marine bacterium, strain GNUM08120, was isolated from Sargassum fulvellum collected from Yeongil bay of East Sea of Korea. The isolate was Gram-negative, aerobic, motile with single polar flagellum, and grew at 1-10% NaCl, pH 5.0-8.0, and $15-37^{\circ}C$. G+C content and the predominant respiratory quinone were 46.13 mol% and Q-8, respectively. The major cellular fatty acids were Summed feature 3 (24.5%), $C_{16:0}$ (21.7%), and $C_{18:1}{\omega}7c$ (12.5%). Based on 16S rRNA gene sequence similarity and DNA-DNA hybridization analyses, strain GNUM08120 was identified as a novel subspecies of Alteromonas macleodii, designated Alteromonas macleodii subsp. GNUM08120. Production of agarase by strain GNUM08120 was likely repressed by the effect of carbon catabolite repression caused by glucose. The crude agarase prepared from 12-h culture broth of strain GNUM08120 exhibited an optimum pH and temperature for agarase activity at 7.0 and $40^{\circ}C$, respectively. The crude enzyme produced (neo)agarobiose, (neo)agarotetraose, and (neo)agarohexaose as the hydrolyzed product of agarose.

• Parasites, Hosts and Diseases
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• v.53 no.3
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• pp.271-277
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• 2015

The genetic diversity of Schistosoma haematobium remains largely unstudied in comparison to that of Schistosoma mansoni. To characterize the extent of genetic diversity in S. haematobium among its definitive host (humans), we collected S. haematobium eggs from the urine of 73 infected schoolchildren at 5 primary schools in White Nile State, Sudan, and then performed a randomly amplified polymorphic DNA marker ITS2 by PCR-RFLP analysis. Among 73 S. haematobium egg-positive cases, 13 were selected based on the presence of the S. haematobium satellite markers A4 and B2 in their genomic DNA, and used for RFLP analysis. The 13 samples were subjected to an RFLP analysis of the S. haematobium ITS2 region; however, there was no variation in size among the fragments. Compared to the ITS2 sequences obtained for S. haematobium from Kenya, the nucleotide sequences of the ITS2 regions of S. haematobium from 4 areas in Sudan were consistent with those from Kenya (> 99%). In this study, we demonstrate for the first time that most of the S. haematobium population in Sudan consists of a pan-African S. haematobium genotype; however, we also report the discovery of Kenyan strain inflow into White Nile, Sudan.

• Journal of Plant Biotechnology
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• v.4 no.1
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• pp.7-15
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• 2002

Eight cDNAs corresponding to fruit-specific genes were isolated from ripened melon through differential screening. Sequence comparison indicated that six of these cDNAs encoded proteins were previously characterized into aminocyclopropane-1-carboxylate (ACC) oxidase, abscisic acid, stress and ripening inducible (ASR) gene, RINC-H2 zinc finger protein, pyruvate decarboxylase, or polyubiquitin. RFS2 and RFS5 were the same clone encoding polyubiquitin. The other cDNAs showed no significant homology with known protein sequences. The ASR homologue (Asr1) gene was further characterized on the cDNA and genomic structure. The deduced amino acid sequence had similar characteristics to other plant ASR. The Asr1 genomic DNA consisted of 2 exons and 1 intron, which is similar to the structure of other plants ASR genes. The promoter region of the Asr1 gene contained several putative functional cis-elements such as an abscisic acid responsive element (ABRE), an ethylene responsive element (ERE), a C-box or DPBf-1 and 2, Myb binding sites, a low temperature responsive element (LTRE) and a metal responsive element (MRE). The findings imply that these elements may play important roles in the response to plant hormones and environmental stresses in the process of fruit development. The results of this study suggest that the expressions of fruit specific and ripening-related cDNAs are closely associated with the stress response.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2009.04a
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• pp.295-303
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• 2009

The annals of Joseon dynasty, especially the volumes of King SeJong(1418-1450 A.D.), were heavily deteriorated by fungi. Investigations on the deteriorating and foxing fungi were carried out. Fungal structures on the beeswax, which were coated on the both side of Han-Ji, were suspected to be involved in the deterioration, and were observed by SEM. Isolation and culturing of these fungi were tried by scrubing swab samples and placing on the artificial media. Culture-independent approaches were used to identify the fungal strains associated with damages of beeswax and foxing of the paper by the analyses based on DNA sequences data from the specific ITS region of rDNA regions. In addition, well-known paper staining fungi(PSF), i.e., Aspergillus terreus var. terreus, Fusarium oxysporum, Chaetomium globosum, Cladosporium cladosporioides, and Alternaria solani, were compared in the mycelial growth and stain on beeswax and papers under different environmental conditions (temperature, light, moisture, etc). Fungal strains isolated from the air samples in the storage room and shelves were identified as Irpex sp., Arthrinium sacchari, Cladosporium tenuissimum, Aspergillus sclerotiorum, Sistotrema brinkmannii, and Hypoxylon bovei var. microsporum The isolated strains were compared in growth and stain patterns on beeswax and papers(Han-Ji, Hwa-Ji, and Yang-Ji) whether these can cause damage or foxing on the annals or not.

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.364-372
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• 2011

The pale chub (Zacco platypus) is generally found in Asian countries, such as Korea, Japan, and China. Nevertheless, very little information exists about the genes involved in the metabolism of xenobiotics in this species. This species is useful in monitoring the environmental impact on various pollutants in freshwater as a sentinel fish species. We cloned the full-length cDNA sequence of xenobiotic metabolizing cytochrome P450 1A (CYP1A) gene from Z. platypus and characterized it. Tissue distribution and timedependent induction of CYP1A were studied by real-time RT-PCR. Induction pattern of CYP1A was studied by exposing the fish to an arylhydrocarbon receptor agonist, ${\beta}$-naphthoflavone (BNF). The liver showed the highest level of expression in basal state as well as BNF- treated fish. However, appreciable levels of expression were also recorded in Gill and kidney and the least level of expression was observed in the eye. The results of the time-course study revealed an induction in the liver, brain, and gills after 6 h and 12 h in most of the tissues. This study provides an insight into the xenobiotics metabolizing system of Z. platypus and offers baseline information for further research related to biomarker, stress, and adaptive response of this ecologically important fish species in the freshwater environment.

• Research in Plant Disease
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• v.11 no.2
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• pp.162-166
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• 2005

Disease progress of gray blight of tea (Camellia sinensis O. Kuntze) cv. Yabukita was investigated during the growing season of 2004 at Boseong Tea Experiment Station, Jeonnam Agriculture Research and Extension Service, Boseong, Jeonnam. The disease began to occur from late June and peaked in late July. Antagonistic bacteria against Pestalotiopsis longiseta, the causal pathogen of causing gray blight of tea plants were isolated from phylloplanes of tea plants. An isolate BD0310 which showed the strongest antifungal activity against the pathogen but nonpathogenic to tea plants was selected as a biocontrol agent for the gray blight. The isolate was identified as Bacillus subtilis based on its cultural, morphological, and biochemical characterization and 16S rDNA sequence analysis.

• Toxicological Research
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• v.6 no.2
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• pp.167-182
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• 1990

Dietary restriction (caloric restriction) is the only intervention which has been reliably shown to extend the maximum life span of warm-blooded animals and delay the many phenomena associated with aging. It is also one of the most effective modulators of toxicity, especially cancer endpoints. In spite of the known modulator effects of caloric restriction, the biological mechanisms responsible for these effects had not been in vestigated until recently. The National Center for Toxicological Research (NCTR), in a collaborative effort with the National Institute of Aging (NIA), initiated a project whereby nine (9) combinations of rodent species/strains and diets were fed both restricted and ad libitum. The NIA's initiative was to identify biomarkers of aging whereas NCTR's initiative was to identify the biological effects associated with the profound effects caloric restriction has in protecting against both spontaneous (age-related) and chemically-induced toxic endpoints. Independent of sex or species, caloric restriction has similar effects on body temperature, oxygen consumption and $CO_2$production. Caloric restriction also decreased lipid glycolysis and metabolism in rats and mice, which suggest decreased production of metabolites which could lead to fatty acid epoxide formation. The age-associated loss of ciradian regulation of intermediate enzymes is also significantly reduced. Moreover, caloric restriction reduced the age-associated feminization of sexually dimorphic liver isozymes, increased several glucocorticoid responsive isozymes, elevated glucagon/insulin ratios, produced less microsomal superoxide and enhanced the capacity for utilzing detoxicating metabolic pathways. Calorically restricted rats have less than half the number of aflatoxin ($AFB_1$)-DNA adducts than ad libitum animals and urinary excretion of $AFB_1$ was increased significantly. Finally, DNA repair mechanisms are enhanced and oncogene expression is decreased in calorically restricted animals.

• Toxicological Research
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• v.17 no.3
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• pp.215-223
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• 2001

Cadmium is an ubiquitous toxic metal and chronic exposure to cadmium results in the accumulation of cadmium in the liver and kidneys. In contrast, acute exposure leads to damage mainly in the liver. Apoptosis induced by cadmium has been shown in many tissues in vivo and in cultured cells in vitro. However, the molecular mechanism of cadmium-induced apoptosis is not clear in hepatocyte. To investigate the induction of apoptosis in the hepatocyte, we used mouse hepatoma cell line, Hepalclc7 cells, and analysed the molecules that involved in cadmium-induced apoptosis. Cadmium induced the genomic DNA fragmentation, PARP cleavage, and activation of caspase-3 like protease. Caspase-9 cysteine protease was activated in a time-dependent manner but caspase-8 cysteine protease was not significantly activated in cadmium-treated Hepalclc7 cells. Cadmium also induced mitochondrial dysfunction including cytochrome c release from mitochondria, change oj mitochondrial membrane potential tranition, and tranlocation of Bax Protein into mitochondria. These results strong1y indicated that the signal Pathway of apoptotic death in cadmium-treated Hepalclc7 cells is modulated by caspase cascade via mitochondria.

• Toxicological Research
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• v.31 no.2
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• pp.173-180
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• 2015

Extract from Gryllus bimaculatus crickets inhibits oxidation at the DNA level, with reduced production of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Microarray analyses were performed with a rat 28K cDNA clone set array to identify the gene expression profiles of aged (10 months old) Wistar Kyoto rats treated for one month with 100 mg/kg G. bimaculatus ethanol extract to assess the effects. The extract produced a meaningful anti-edema effect, evident by the inhibition of creatinine phosphokinase activity. The weights of abdominal and ovarian adipose tissues were reduced and the proportion of unsaturated fatty acids in adipose tissues was increased in an extract dose-dependent manner. Compared with untreated control rats, rats treated with the extract displayed the upregulation of 1053 genes including Fas (tumor necrosis factor receptor superfamily, member 6), Amigo3 (adhesion molecule with an immunoglobulin-like domain), Reticulon 4, 3-hydroxy-3-methylglutaryl-coenzyme (Hmgcr; a reductase), related anti-fatigue (enzyme metabolism), and Rtn antioxidant, and the downregulation of 73 genes including Ugt2b (UDP glycosyltransferase 2 family), Early growth response 1, and Glycoprotein m6a. Data suggest that G. bimaculatus extract may have value in lessening the effects of aging, resulting in a differential gene expression pattern indicative of a marked stress response and lower expression of metabolic and biosynthetic genes.