• Korean Journal of Microbiology
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• v.37 no.4
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• pp.265-272
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• 2001

The diversity of acid-tolerant epiphytic bacterial communities on deciduous oak tree (Quercus dentate Thunb.) leaves was examined both in the natural forest area with a clean air and in the industrial estate to assess effects of acidic depositions to the phyllosphere using 16S rDNA sequence data. A total of 444 acid-tolerant epiphytic bacterial clones were obtained, resulting in 17 phylotypes by performing a analysis of restriction fragment length polymorphism (RFLP) for PCR-amplified 16S rDNA products. A very low diversity of dominating acid tolerant bacterial communities in both areas was found, just 2 subphyla groups, $\gamma$-Proteobacteria and low-G+C gram-positive bacteria. As tree leaves grow older, diversities of acid-tolerant bacteria on them significantly increased. The community structure of acid-tolerant epiphytic bacteria consisted of Pseudomonas and Enterobacteriaceae groups in the $\gamma$-Proteobacteria subphylum, and Streptococcaceae and Staphylococcus groups in the low-G+C gram-positive bacteria subphylum. The direct influence of acidic depositions on bacterial phylogenetic composition could not be detected especially when higher taxonomic levels such as subphylum, but at narrower or finer levels it could be observed by a detection of Xanthomonadales group belonged to the $\gamma$-Proteobacteria only in the industrial area and of Acetobacteraceae group belonged to the $\alpha$-Proteobacteria. There remains that these specific acid-tolerant epiphytic bacterial groups could be used as indicators for assessing effects of acidic depositions on the phyllosphere.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.272-276
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• 2003

Sapgyo Lake is an artificial freshwater reservoir which is located to the midwest of Korea and is the main water reservoir for industry and agriculture of the region. In this study we investigated environmental factors and the change of bacterial community with the influence of surrounding inflow water and the seasonal variation using the molecular ecological approach. Water samples were collected at front of the dike in May and August, 2001. Bacterial genomic DNAs were extracted directly and purified for the amplification of bacterial 16S rDNA. Clone libraries of the 16S rDNA were constructed using pGEM-T easy vector and RFLP analysis was performed to make a group as OTUs with 4 base recognizing enzymes (MspI and HaeIII). The estimated values of richness in August sample was higher than in May. Thirty-three of 153 clones in May and thirty-eight of 131 clones in August were sequenced from forward region of bacterial 16S rDNA for about 600~800 bp. Proteobacteria, Cytophaga, gram positive bacteria and Verrucomicrobia were observed both months. Especially, Planctomyces, cyanobacteria and chloroplast appeared in August when algal bloom occurred. On the whole investigation, Sapgyo lake showed a typical community structure of estuarine and was influenced by heterochthonous organic matters from the surrounding stream.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.13-22
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• 2003

Growth Hormone (GH) gene is a member of gene family through the evolutionary process from a small common ancestral gene by a series of gene duplications. The role of the GH in growth and performance controls has been extensively studied in human, mice and livestock. Many researchers have considered GH as a strong candidate gene for evaluation of genetic polymorphisms that could be associated with economic traits in cattle. We report here a novel missense mutation within the exon 5 of the bovine Growth Hormone (bGH) gene. We could amplified 522 bp fragments from eight unrelated Hanwoo cattle by PCR, then, subsequently cloned and sequenced. An Msp I RFLP corresponding to a C to T transition was observed at position 2258 nt. From this result, we could predict a missense mutation (Arg to Trp) at codon 166 in a highly conserved region among many mammals. Codominant Mendelian segregation of the two alleles, Msp I (+) and Msp I (－), was observed in two full-sib F2 families (n = 32, African taurine Bos taurus ${\times}$ African zebu Bos indicus) and eight half-sib Hanwoo families. For the availability of genetic marker, we have performed PCR-RFLP with a large number of individual animals from 15 different cattle breeds (European and Asian taurines, and African indicines). Consideration of breed frequencies of Msp I (－) allele in relation to breed type and their geographic origins, shows higher frequencies in humped breeds or Asian cattle breeds than in humpless or European breeds. This result indicates that the missense mutation can be contributed the functional significance such as the signal transduction through the receptor binding, also may be used as a marker for selection of the economic traits in Hanwoo.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.169-176
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• 2010

A pilot-scale wastewater treatment plant combined with rotating biological contactor and tapered aeration reactors was operated with the wastewater discharged from a food factory for 5 months. The bacterial communities of this plant were investigated by terminal restriction fragment length polymorphism (T-RFLP) and phylogenetic analysis of 16S rRNA genes. In spite of high concentration of nitrogen and phosphorus as well as organic carbon, removal efficiency of chemical oxygen demand, total nitrogen, and total phosphorus was 98%, 93%, and 95%, respectively. Bacterial community at the initial operation stage was clearly distinguished from that of the stable operation stage. The most predominant phylum in the sample of stable stage was Bacteroidetes. Major population of operation period was Haliscomenobacter, Sphaerotilus, and candidate division TM7, which were classified as filamentous bacteria. However, sludge bulking caused by these bacteria was not observed. The population that has a close relationship with Haliscomenobacter increased during the stable operation stage, emerging as the most predominant group. These results suggest that the filamentous bacteria participated in nutrient removal when using rotating biological contactor and tapered aeration reactor.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.260-269
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• 2005

Taxonomic studies on morphological, principal component analysis (PCA), palynological, RAPD and PCR-RELP analysis were conducted to intraspecific relationships of Rubus oldhami. Three types of Rubus oldhami based on the flower characters such as petal length and number were used in this study. Among the 14 morphological characters, perianth length, calyx lobe length, apical leaflet shape and leaflet length were used to distinguish for each type. The pollen characters such as shape, aperture number, surface sculpture were showed very similar among three types. Eight primers out of 20 arbitrary primers were screened for three types, and were revealed 33 ($60\%$) polymorphic bands. The phonogram by RAPD data showed incongruent with morphological analysis. Even though ten restriction endonucleases produced 20 restriction sites, polymorphic bands were not observed. Based on the results, three types of Rubus oldhami divided well by morphological characters, but pollen and DNA data were not supported. Therefore, type 1 and 2 which different from type 3 by flower characters considered as a temporary hybrid or ecotype because of their similar habitats.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.204-210
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• 2015

Makgeolli is made from rice or flour, yeast, and nuruk, a fermentation starter. The flavor of makgeolli is affected by sugars, amino acids, organic acids and volatile flavor compounds produced by various microorganisms. In this study, lactic acid bacteria (LAB) were isolated from unsterilized makgeolli samples collected from several provinces in Korea, and then later identified. Under anaerobic conditions, LAB density ranged from $5.0{\times}10^6$ to $1.5{\times}10^8CFU/mL$; yeast density ranged from $2.5{\times}10^7$ to $1.5{\times}10^8CFU/mL$. Of the LAB isolated from makgeolli, 1,126 were analyzed using restriction fragment length polymorphism (PCR-RFLP) analysis of 16S rRNA, which allowed for classification into five groups. Of the 1,126 LABs tested, 130 produced ${\gamma}$-aminobutyric acid (GABA).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.712-721
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• 1997

The objectives of this study were; (1) to identify and localize QTLs for resistance to soybean cyst nematode(SCN) race 5 on RAPD map, (2) to idntify the magnitude and mode of inheritance for each QTL, and (3) to identify the best combinations of QTLs for resistance to SCN race 5. Based on the univariate regression analysis, we detected 26 markers(22 RAPD and 4 RFLP) which showed significant association(P<0.05) with resistance to SCN race 5. From MAPMAKER /QTL analysis, we identified two regions (LGC-20 and Group 2) for resistance to SCN race 5. The QTL that was localized at 8.0 cM from pK418C on LGC-20 showed a recessive mode of inheritance and the QTL that was localized between W03 and E02$^3$ on Group 2 showed a dominant mode of inheritance. Two pairs of flanking markers (E02$^3$ and W03, pK418C and pK418E$_1$) and one unlinked RAPD marker, G10$^1$ were used for multiple regression analysis. Marker combination which was composed of 4 markers, E02$^3$, G10$^1$, W03, and pK418E$_1$, explained the highest amount of phenotypic variation by SCN (35.2％). Further research for the identification of QTLs for resistance to SCN race 5 to explain larger portion of phenotypic variation is needed.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.182-186
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• 2004

Morphological observation of roots and molecular technique were used to investigate the symbiotic relationships between arbuscular mycorrhizal (AM) fungi and ginseng roots. Korean ginseng, Panax ginseng, was collected from 8 sites in Korea. Colonization pattern of AM fungi in ginseng roots was determined as an Arum type under light microscopes. Nested PCR using AM fungal specific primers was employed to amplify a partial region on 18s rDNA of AM fungi from the root extracted mixed DNA. The amplified DNA was cloned and analyzed by random fragment length polymorphism (RFLP) with restriction enzymes, AluI, HinfI and AsuC21. One from each RFLP pattern was selected for sequencing. A total 16 clones were sequenced and identified as 2 species of AM fungi; Paraglomus brasilianum and Glomus spurcum. Paramglomus brasilianum was found from most of the ginseng roots, in this syudy suggesting that this species of AM fungi could have specific relationship with the ginseng root. Possible roles of AM fungal species in ginseng roots are discussed.

• Korean Journal of Poultry Science
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• v.32 no.4
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• pp.239-244
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• 2005

Uncoupling protein(UCP) is expressed exclusively in brown adipose tissue(BAT). It is blown to uncouple phosphorylation from oxidation and hence to be involved in energy metabolism and heat production, especially under cold exposure. In the present study, we identified single nucleotide polymorphism(SNP) in exon 3 of avUCP gene in Korean native chicken(KNC) population. It was detected a SNP T+1316C in exon 3 of avUCP gene by sequence analysis in KNC population. For PCR-RFLP analysis of the SNP T+1316C, used by AP III restriction enzyme. The result of PCR-RFLP analysis showed that allele T has two fragments of 255 bp and 86 bp, and allele C has only one fragment of 341 bp. The genotype frequencies were TT type, 0.7875; TC type, 0.1875 and CC type, 0.025; and the frequencies of allele T and C were 0.881 and 0.119, respectively in KNC population. Next study was conducted to investigate the effect of the SNP in avUCP gene on economic traits in the KNC population. The TT genotype had a significant higher daily percent lay(84.61) than CC genotype(p<0.05) in KNC population. This study may be useful for genetic studies of avCUP gene and selection on daily percent lay of KNC.

• Journal of Life Science
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• v.17 no.12
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• pp.1622-1626
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• 2007

This study was conducted to identify useful single nucleotide polymorphisms (SNPs) and determine their association with economically important traits in pig population. Four candidate gene analyses have identified important chromosomal regions and major genes associcated whit economic traits of the pig. For application of the chromosomal information to the pig industry using DNA technology, SNP markers were developed by comparative re-sequencing of polymerase chain reaction (PCR) products of 4 candidate genes (CSF2, IL4, MYOD, RIP140). PCR restriction fragment length polymorphism (PCR-RFLP) assays were developed for these 4 SNPs and used to genotype Berkshire pig populations in Korea.