• Korean Journal of Microbiology
• /
• v.46 no.4
• /
• pp.405-408
• /
• 2010

Diversity of myxobacteria in five soil samples from Asansi and Uponeup in Korea was explored by means of polymerase chain reaction (PCR) using primers that specifically bind 16S rDNA of myxobacteria. DNA sequence analysis of 76 PCR fragments containing myxobacterial 16S rDNA revealed five putative novel myxobacterial genera whose 16S rDNA sequences shared <95% sequence identity with those of the type strains. This finding indicates the presence of many uncultured and unidentified myxobacterial species in Korean soil.

• Journal of Animal Science and Technology
• /
• v.46 no.3
• /
• pp.307-314
• /
• 2004

Xenotransplantation of porcine organs has the potential to overcome the severe. shortage of human tissues and organs available for human transplantation. The swine represents an ideal source of such organs because of their plentiful supply and their numerous anatomical and physiological similarities to the human. However, this procedure also carries with a number of safety issues relating to the zoonotic infections. Porcine endogenous retrovinJses(PERVs), \Wich are germ line transmitted and persist without symptoms in the pigs, are most concerning zoonotic viroses. In order to analyze the prevalence of PERV in domestic pigs, four kinds of pigs'(Landrace, Berkshire, Yorkshire, and Duroc) genomic DNA were isolated from their hair follicles. PCR analysis was carried out for detection of PERVs using subgroup A/B/C and E pol sequence primers. All pigs (20 heads) tested had high copy number of PERVs within genomes. Subgroup A/B/C and E pol gene sequences from 20 isolates were determined by direct sequencing. Sequence analysis showed pol sequences are highly conserved among intra- and inter-subspecies(99.l and 98.8%, respectively). As a first report of PERV prevalence in Korea pigs, our data would be the basic concepts of PERV transmission study in xenotransplantation.

• Biomedical Science Letters
• /
• v.4 no.1
• /
• pp.1-9
• /
• 1998

A Corynebacterium diphtheriae iron-repressible gene dirA, that was homologous to TSA of Saccharomyces cerevisiae and AhpC subunit of Salmonella typhimurium alkyl hydroperoxide reductase, was amplified with PCR and expressed in E. coli. The DirA purified from the transformed E. coli crude extracts prevented the inactivation of enzyme caused by metal-catalyzed oxidation (MCO) system containing thiols but not by ascorbate/Fe$^{3+}$/$O_2$ MCO system. The DirA concentration, which inhibited the inactivation of glutamine synthetase by 50% (IC$_{50}$) against MCO system, was 0.12 mg/ml. The multimeric forms of DirA were converted to the monomeric form in SDS-PAGE under the thioredoxin system comprised of NADPH, Saccharomyces cerevisiae thioredoxin reductase, and thioredoxin. Also, DirA showed thioredoxin dependent peroxidase activity. All of these results were consistent with the characteristics of a thiol specific antioxidant (TSA) protein having two conserved cysteine residues.

• Development and Reproduction
• /
• v.5 no.2
• /
• pp.107-114
• /
• 2001

The recent reports that endocrine disruptors(EDs) bring about abnormalities in reproductive organs and functions of invertebrates suggest that mammals be affected by the EDs. The present study examined the influence of 2-bromopropane(2-BP) by looking at the sexes of litters in mouse. The expression of sex-related genes during sex differentiation was also investigated in the fetus of mouse. The male and female mice were infused with 2-BP for 3 weeks before mating. The litters were sexed at the weaning time from the 4 different groups. The sex-related genes were identified by RT-PCR from the fetuses at gestation 10 days. The sequences of the genes were analysed by comparing to those of other animals. The mean numbers of litters survived by the weaning time were slightly reduced in the only group of both female and male mice treated with 2-BP. The female litters were greater than male litters in the only group of female treated with 2-BP. The other groups showed male litters greater than female litters. The sex-related genes, SRY, DAX1, SF1 , and AMH genes were identified and sequenced, showing 416, 466, 326, 389 base pairs, respectively. All of the genes had the homology of 89～90％ with rat and 81～92％ with human within the range of bases identified. They were expressed at the time of sex determination. Therefore, it appears that 2-BP somewhat affects the reproductive activity of adult mouse. Influence of 2-BP on the reproductive function is expected to be studied through the expression of the sex-related genes.

• Korean Journal of Agricultural Science
• /
• v.34 no.2
• /
• pp.99-109
• /
• 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
• /
• v.20 no.12
• /
• pp.1743-1749
• /
• 2010

A research group demonstrated that the 37 kDA protein of Edwardsiella tarda, a causing causative agent of edwardsiellosis in fish, exhibited high antigenicity in Japanese flounder. The research group also showed that the N-terminus amino acid sequences of the 37 kDa protein were mapped to the N-terminus of GAPDH (glyceraldehyde-3-phosphate dehydrogenase). Using degenerated primer sets based on the known N-terminus sequence, the corresponding E. tarda DNA was amplified and cloned. The nucleotide sequences of the cloned gene revealed high homology with a bacterial gene for GAPDH, as we was expected. The amino acid sequence of E. tarda GAPDH (etGAPDH) revealed a <70% similarity with GAPDH proteins in other Enterobacteriaceae. With the application of artificial protein overexpression system in Escherichia coli, the recombinant etGAPDH (rGAPDH) was produced and purified. In this study, Using the purified rGAPDH, the etGAPDH specific polyclonal antibody has been was generated using the purified rGAPDHin this study. The immunoblotting analyses demonstrated that the location of the GAPDH protein is located with the association of is associated with the envelops of E. tarda. The rGAPDH was administrated into Japanese flounder via IP route for evaluation of the protective ability. Although the specific antibody titer against etGAPDH was increased about 3-fold after 4 weeks post-vaccination, the survival rates of vaccinated Japanese flounder and the control group with wild type E. tarda was were 12.5% and 0%, respectively. Our results indicated that rGAPDH is immunoreactive antigen but that it will not generate protective immunity in Japanese flounder.

• Korean Journal of Microbiology
• /
• v.51 no.2
• /
• pp.141-147
• /
• 2015

Four halophilic bacteria were isolated from a salt water tank of more than 25% above salinity used for production of salt. HJS1 and HJS6 strains were identified as having ${\beta}$-glucosidase producing capabilities at high salinity. ${\beta}$-Glucosidase produced from these bacterial strains showed the best activity at 56-79 U/ml in NaCl (0-5%), showing the highest ${\beta}$-glucosidase activity at NaCl 3%. A salt tolerant ${\beta}$-glucosidase can maintain at least 75% activity of the enzyme in 0-20% NaCl concentration. The 16S rRNA gene sequences of strains HJS1 and HJS6 shows 99.8% similarity with Roseivivax roseus $BH87090^T$. Those sequences were registered as AB971835 and AB971836 in the NCBI GenBank. DNA-DNA hybridization test revealed that both strains showed 90.1 to 90.3% hybridization values with R. roseus $BH87090^T$, which was the closest phylogenetic neighbor. Major Cellular fatty acids of strains HJS1 and HJS6 were $C_{16:0}$, $C_{18:1}$ ${\omega}7c$, $C_{19:0}$ cyclo ${\omega}8c$ and 11-methyl $C_{18:1}$ and the major quinone was Q-10. Their fatty acid composition and quinone were very similar to Roseivivax roseus $BH87090^T$. Meanwhile, Roseivivax roseus $BH87090^T$ did not produce any ${\beta}$-glucosidase. Based on the molecular and chemotaxonomic properties, strains HJS1 and HJS6 were identified as members of Roseivivax roseus.

• Journal of Life Science
• /
• v.12 no.3
• /
• pp.264-273
• /
• 2002

We have isolated and artificially expressed three cDNA clones of Capsicum annuum PR5 genes for elucidating the antifungal activity against Phytophthora capsici which contracted a hot pepper root rot in field condition. Three divergent PR5 proteins from hot pepper were designated as CAPR5-1 and CAPR5-2 from susceptible cultivar (Subicho) as well as CAPR5-3 from resistant cultivar (CM331) in response to P. capsici. The cDNA similarity was found over 80% of identity among the three CAPR5s, and deduced amino acid sequence was characterized that all of CAPR5s contained 16 cysteine residues which possibly had a significant role in the structural formation. The result of genomic DNA blot showed that CAPR5-1 and CAPR5-2 existed as single copy in the Subicho genome. Three recombinant CPARs in E. coli were identified by SDS-PACE, and each expressed protein was treated on the PDA medium which contained cultured pathogens. Although three CAPR5 proteins did not affected the hyphal growth of Glomerella glycines and Colletotrichum fagenarium, CAPR5-1, CAPR5-2, and CAPR5-3 showed a specific antifungal activities against P. capsici.

• Annual Conference on Human and Language Technology
• /
• 1995.10a
• /
• pp.228-232
• /
• 1995

음절과 글자의 내부구조에 대한 언어학적 심리학적 논의들을 개관하였다. 영어의 음절구조에 대한 연구들은 초두자음/각운 구조를 지지하고 있다. 한편 한국어의 음절과 글자의 내부구조에 대한 최근의 연구는 영어에서 얻어진 결과들과 다른 결과를 얻고 있다. 자모대체 과제를 사용한 이 연구에 의하면, 글자유형에 관계없이 종성자모의 대체시간이 초성자모의 대체시간보다 짧았다. 이러한 결과는 음절에 대응하는 글자의 내부구조로서 초중성자모/종성자모 구조를 지지하고 있다. 선행연구 결과들을 바탕으로 음운단위와 표기단위의 상동성, 그리고 언어특유적 음절구조의 가능성에 대해서 논의하였다.

• Proceedings of the KAIS Fall Conference
• /
• 2007.05a
• /
• pp.270-272
• /
• 2007

본 연구는 서산 6쪽 마늘로부터 완전장 유전자 은행의 제작과 이를 통해서 확보된 1,000여개 재조합 클론에 대한 염기서열 결과를 web-based database를 통한 상동성 분석으로 부터 서산 마늘의 발현 유전자에 대한 생물정보학적 분석에 관해 것이며 본 연구로 부터 마늘의 대표적 생리활성 물질인 allicin의 생성에 관여하는 효소인 allinase의 cDNA를 클로닝 및 완전 염기서열을 해석하였으며 allinase 유전자의 genomic structure 에 대한 일부의 결과를 확보하였다. 또한 다양한 생물종에서 연구 되어지고 있는 생리활성 단백질인 lectin 유전자 cDNA를 클로닝하여 완전 염기서멸을 분석하고, 6xHis Tag올 통한 재조합 단백질을 대장균에서 E.coli에서 발현시켰다.