• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.360-367
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• 2006

The endoinulinase gene (inu1) from Pseudomonas mucidolens was expressed on the cell surface of Saccharomyces cerevisiae by fusing with Aga2p linked to the membrane anchored protein, Aga1p. The inu1 gene of P. mucidolens was subcloned into the surface display vector, pCTcon (GAL1 promoter). The constructed plasmid, pCTENIU (8.5kb), was then introduced to S. cerevisiae EBY100 cells and the yeast transformants selected on synthetic defined media lacking uracil and inulin-containing media. The inu1 gene under the control of the GAL1 promoter was successfully expressed in the yeast transformants, and the surface display of endoinulinase confirmed by immunofluorescence microscopy, along with its enzymatic ability to form inulooligosaccharides (IOSs) from inulin. The total endoinulinase activity reached about 2.31 units/ml when the yeast transform ants were cultivated on a YPDG medium. To efficiently hydrolyze the inulin, various reaction conditions were examined, including the pH, temperature, and inulin source. The optimized conditions were then determined as follows: pH, 7.0; temperature, $50^{\circ}C$; inulin source, Jerusalem artichoke. Under the optimized condition and 46 units of endoinulinase per g of inulin, IOSs started to be produced after 10 min of enzymatic reaction. The highest yield, 71.2% of IOSs, was achieved after 30 h of reaction without any significant loss of the initial enzyme activity. As a result of the reaction with inulin, IOSs consisting of inulobiose (F2), inulotriose (F3), inulotetraose (F4), and inulopentaose (F5) were produced, and F4 was the major product.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.300-304
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• 1991

Several experiments were conducted to elucidate a possibility of sweet sorghum, sugar beet and sugar cane as the resources of bio-energy which were collected from Philipine, India, Japan and Gene -bank in Korea. The experiments were carried out in Chinju, Korea from 1986 to 1988. When sweet sorghum cultivars were taken from 70 to 118 days after sowing on May 20, 1988 upto heading stage, the sugar content of stem was 6 to 14% and yielded 4 to 10ton per l0a in terms of the total fresh weight of plant. Sugar beet root contained 9.2 to 19.8% in sugar producting 3,542 to 6. 397kg per l0a. Meanwhile. the sugar content in stem of sugar cane was 15.2 to 16.7% and final growth the late October in this particular region. Particularly, F1 hybrid cultivar(s-l) of sweet sorghum could be harvested twice in a year. The alcohol quantity obtained from the juice of sweet sorghum was 180$\ell$ per l0a and was increased as sowing date was earlier. The results suggested that it would be possible to utilize the sugar crops as bio-energy resources using improved cultural methods and effective fermentation techniques.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3811-3815
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• 2014

Background: Colorectal cancer (CRC) is the worldwide disease which causes enormous losses every year. Recent studies suggested that environmental and gene factors might be the etiologies in increasing the risk of morbidity. Nitric oxide synthase 3 (NOS3) gene polymorphisms are said to be associated with CRC risk but the conclusion is still controversial. Materials and Methods: Pubmed and HuGENet databases up to December 2013 were used in this meta-analysis. Three different certain genotypic models were applied, namely dominant (AA+AC versus CC), recessive (AA versus AC+CC), per-allele analysis (A vs C). In addition, information on tumor sites and pathologic stages was collected. The strength of associations was assessed through combining odds ratio (OR) and 95% confidence interval (CI). Results: Finally, five and three studies about the rs1799983 and rs2070744 were covered in the analysis with 2,745 cases and 2,478 controls. Three models were applied, but no significant association was found for NOS3 G894T/rs1799983 (dominant: OR=0.999, 95%CI=0.797-1.253, $I^2$=63.8%; recessive: OR=0.924, 95%CI=0.589-1.450, $I^2$=59.3%; allele analysis: OR=0.979, 95%CI=0.788-1.216, $I^2$=74.9%) and T-786C/rs2070744 (dominant: OR=1.138, 95%CI=0.846-1.530, $I^2$=67.9%; recessive: OR=0.956, 95%CI=0.708-1.291, $I^2$=0.0%; allele analysis: OR=1.110, 95%CI=0.865-1.425, $I^2$=69.4%). The same results were also obtained for tumor sites and pathologic stage subgroups. After further analyzing the NOS3 gene, rs1799983 as the tag- and functional SNP was presented. Conclusions: On the basis of this meta-analysis and the characteristics of the NOS3 gene, we suggested rs1799983 might be a key locus associated with CRC risk. Further prospective studies were needed to make more comprehensive explanation of the associations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.74-77
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• 1986

The male sterility gene of IR36ms was transferred to four Korean rice cultivars Gayabyeo, Nampungbyeo Sinkwangbyeo and Suweon 296 by five times back crosses. From the BC$_4$F$_2$, the genetic male sterile rices having the backgrounds of the Krean cultivars, Gayabyeo ms, Nampungbyeo ms, Sinkwangbyeo ms and Suweon 296 ms were selected. No differences in number of panicles per hill, number of florets per panicle, heading date and length of panicle, were found between the male sterile lines and their parental cultivars in the four series of male sterile rices. The culm length of the male sterile lines was shorter than that of their parental cultivars in the four male sterile rice. Significant difference in out cross rate was found from the genetic male sterile rices having different back-grounds even though they have the same male sterility gene. The out cross rates of Gayabyeo ms, Nampungbyeo ms, Sinkwangbyeo ms and Suweon 296 ms were 11.5%, 13.1 %, 1.9% and 12.7% respectively. No difference in out cross rate was found on the genetic male sterile plants planted from I 5cm to 90cm from the pollinater.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.84-85
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• 2006

This study was carried out to ascertain phylogenetic status of long-tail chicken which found recently in Korea and was presumed to be a kind of Korean Natives. 10 loci microsatellites were analysed for 449 birds of 11 groups and 2 region of mitochondrial DNA were sequenced for 135 birds of the same groups, that consist of 3 introduced breeds and 8 Korean Natives including 3 long-tail chicken. In mean numbers of alleles per locus(MNA) for microsatellites, long-tail chicken were smaller (2.60${\sim}$3.20) than the others, but in heterozygosities, were higher(0.4087${\sim}$0.5375) than others that were the same level of MNA. And in the neighbor joining bootstrap tree drawing by Nei's standard distance, they made a cluster with some Korean Native groups. All of the nucleotide sequences of mitochondrial cytochrome b gene and D-loop were classified into 23 haplotypes. In long-tail chicken, the haplotypes were 3 kinds, and were different among the groups (LTA, LTB and LTD). Resultly, it was supposed that 3 groups of the long-tail chicken be all a kind of Korean Natives.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.168-175
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• 2007

We report here on the cultivation of numerous novel bacterial species from a eutrophic freshwater pond. A total of 60 strains, 15 strains per each culture medium, were obtained from the surface of a eutrophic freshwater pond by employing a conventional dilution-plating method with four different kinds of culture media, including R2A, 1/10R2A, PCA, and 1/10PCA. Among the 60 strains isolated, 27 strains showed less than 97% 16S rRNA gene sequence similarities to validly published species, and thus they are considered to comprise 19 novel species. Of the 27 strains assigned to the novel species, the majority of the strains (20 strains) were affiliated with the Alphaproteobacteria and Betaproteobacteria. The remaining 7 strains were affiliated with the Gammaproteobacteria, Firmicutes, Actinobacteria, and Deinococci. Because we have isolated 19 novel species from a usual freshwater pond using a conventional culturing technique, our results suggest that an unexplored ecosystem, even if it looks like a common ecosystem found elsewhere, harbors diverse unidentified microbes, which will be definitely further characterized.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.536-543
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• 1995

Multicopy integration vector is a very useful vector system in that they can be integrated into chromosomal DNA in several copies and stably maintained under non-selective conditions. To develop a multicopy integration vector system in the yeast Yarrowia lipolytica, P-type ribosomal DNA was cloned from Y lipolytica. A HindIII-BglII fragment of the cloned rDNA and a promoterless URA3 gene were inserted into pGEM1, generating multicopy integration vectors, pMIYL-1 and pMIYL-2. The rDNA fragment is for targeted homologous recombination between the vector and the chromosomal DNA of Y. lipolytica, and the promoterless URA3 gene is a defective selection marker for inducing multicopy integration. pMIYL-1 and pMIYL-2 have an unique restriction enzyme site, KpnI, and two unique restriction enzyme sites, KpnI and EcoRI, repectively, which can be used for targeting of the vectors into the rDNA of Y. lipolytica chromosomal DNA. After transformation of the vectors into Y. lipolytica, copy number and stability were analyzed by Southern hybridization. The vectors were found to be present in less than 5 copies per cell and were stably maintained during growth in non-selective media.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.2
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• pp.179-183
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• 2002

The fragment in intron I of FSH-${\beta}$ gene was amplified by PCR. According to the polymorphism, we analyzed the distribution of FSH-${\beta}$ retroposon in different pig breeds; its inheritance pattern in Large White${\times}$Meishan reference family; and the association of FSH-${\beta}$ retroposon with litter size, female reproductive organs measurement, ultrasonic backfat and other traits. The results showed that almost each Chinese indigenous pig had the retroposon, while foreign pig breeds rarely had; the frequencies of porcine FSH-${\beta}$ retroposon were strongly associated with breeds (p<0.01); the pattern of inheritance was consistent with Mendelian fashion; total number born (TNB) and number born alive (NBA) were increased per FSH-${\beta}$ retroposon (p<0.01) with additive effects of 1.2-1.8 and 1.4-1.8 pigs/litter, respectively; between the FSH-${\beta}$ retroposon carriers and non-carriers, there was an insignificant difference in the measurement of female reproductive organs, body weight at birth, backfat thickness, loin meat height, lean meat percentage, teat number, days to 100 kg, and average daily gain.

• Journal of Crop Science and Biotechnology
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• v.10 no.4
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• pp.237-242
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• 2007

Genome duplication(i.e. polyploidy) is a common phenomenon in the evolution of plants. The objective of this study was to achieve a comprehensive understanding of genome duplication for SNP discovery by Thymine/Adenine(TA) cloning for confirmation. Primer pairs were designed from 793 EST contigs expressed in the roots of a supernodulating soybean mutant and screened between 'Pureunkong' and 'Jinpumkong 2' by direct sequencing. Almost 27% of the primer sets were failed to obtain sequence data due to multiple bands on agarose gel or poor quality sequence data from a single band. TA cloning was able to identify duplicate genes and the paralogous sequences were coincident with the nonspecific peaks in direct sequencing. Our study confirmed that heterogeneous products by the co-amplification of a gene family member were the main cause of obtaining multiple bands or poor quality sequence data in direct sequencing. Counts of amplified bands on agarose gel and peaks of sequencing trace suggested that almost 27% of nonrepetitive soybean sequences were present in as many as four copies with an average of 2.33 duplications per segment. Copy numbers would be underestimated because of the presence of long intron between primer binding sites or mutation on priming site. Also, the copy numbers were not accurately estimated due to deletion or tandem duplication in the entire soybean genome.

• Korean Journal of Medicinal Crop Science
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• v.13 no.2
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• pp.69-74
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• 2005

Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name 'Cheongsong' is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K.pictus and K. pictus variant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm=0.857) indicated that gene flow was not extensive among Korean populations of K.pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K.pictus and K.pictus variant populations may have played roles in shaping the population structure of this species.