• Korean Journal of Microbiology
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• v.34 no.4
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• pp.236-242
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• 1998

While bacteriophage P2-P4 system is very useful experimental tool for the study of viral capsid assembly, there is no useful plasmid vector for the DNA manipulation in bacteriophage P2-P4 system. In this study, a new vector plasmid, P4 ash8 (sid71) kmr, was constructed by swapping the non-essential region of P4 DNA for kanamycin resistance(kmr) gene cassette of plasmid pUC4-K. P4 ash8 sid71 was starting material for the construction, since it tends to be maintained as a plasmid in the absence of the helper phage. The total size of this chimera was designed to be packaged into P4 or P2 size heads with induction by P2 infection. The conversion of plasmid P4 ash8 (sid71) kmr to bacteriophage was proved by burst size determination experiment and CsCl buoyant equilibrium density gradient experiment. Integrase destructed P4 derivative, P4 ash8 sid71 kmr intS, was able to be constructed easily by in vitro DNA manipulation of P4 ash8 sid71 kmr. The plasmid stability experiment with P4 ash8 sid71 kmr if/tS showed that the integrase of P4 affects the stable maintenance of plasmid P4 state.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.24-30
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• 2018

Norovirus infection is a leading cause of nonbacterial gastroenteritis outbreaks. New variants of GII.4 have emerged approximately every 2~3 years and have caused norovirus gastroenteritis pandemics globally. In this study, analysis and molecular genetic characteristics of the norovirus gastroenteritis outbreaks 2,917 samples in Gyeonggi-Do from 2014 to 2015. As a result, 247 samples out of 2,917 samples are positive for norovirus. Norovirus molecular genetic characteristics of the GI 8 types (GI-1, 2, 3, 4, 5, 6, 12, 14), GII 10 types (GII - 2, 3, 4, 5, 6, 11, 12, 14, 16, 17). Genome sequences of isolated noroviruses were similar to those of new GII.17 Kawasaki 2014 variants with 96.6 identity, suggesting that these viruses were imported from overseas. 44% of virus incidence was originated from school meal service. Therefore, a continuous monitoring and school sanitation should be required for preventing a massive virus outbreak.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.147-152
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• 1998

AL1-gene, necessary for the replication of the genome of a gemini virus TGMV, was inserted in the opposite direction to the promoter CaMV35S resulting in the construction of a plant transformation binary vector pAR35-2. The vector pAR35-2 contains the chimeric gene cassette involving the duplicated promoter CaMV35S, opposite direction of AL1-gene fusioned with hygromycin resistant gene, and the gene cassette of the neomycin phosphotransferase II gene. The plasmid was transferred to tobacco and tomato plants by leaf disk infection via Agrobacterium. The transgenic plants were selected and grown on the MS-agar medium containing kanamycin and hygromycin. The shoots induced from the calli were regenerated to the whole transgenic plants. The antisense AL1-gene was detected in the genomic DNA isolated from the leaves by using the PCR mediated Southern blot analysis. The expression of the antisense AL1-gene was also observed using the RT-PCR mediated Southern blot analysis. The observation of chloroplasts in guard cell pair indicated that the transgenic tomato plants were diploid.

• Parasites, Hosts and Diseases
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• v.49 no.3
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• pp.331-335
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• 2011

A tick survey was conducted to determine the relative abundance and distribution of ticks associated with selected mammals in the Republic of Korea (ROK) during 2008-2009. A total of 918 ticks were collected from 76 mammals (6 families, 9 species) captured at 6 provinces and 3 Metropolitan Cities in ROK. Haemaphysalis longicornis (54.4%) was the most frequently collected tick, followed by Haemaphysalis flava (28.5%), Ixodes nipponensis (7.6%), Ixodes pomerantzevi (4.8%), Ixodes persulcatus (4.6%), and Haemaphysalis japonica (0.1%). Adults (57.0%) and nymphs (28.7%) of Ixodes and Haemaphysalis spp. were collected most frequently from medium or large mammals in this survey, while few larvae (14.3%) were collected. Hydropotes inermis was the most frequently captured mammal (52.6%), with a 16.4 tick index and 5 of 6 species of ticks collected during this survey. H. longicornis (69.7%) was the predominant tick collected from H. inermis, followed by H. flava (22.2%), I. persulcatus (6.1%), I. nipponensis (1.8%), and H. japonica (0.2%).

• Biomolecules & Therapeutics
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• v.11 no.4
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• pp.257-264
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• 2003

Carnitine, hydroxycitric acid, and soy peptide have been known to be anti-obesity agents. The purpose of this study was to evaluate the combined effects of carnitine, hydroxycitric acid, and soy peptide mixture as a potential anti-obesity supplement in overweight women. Overweight premenopausal women (n=33; PIBW>110; 20 to 39 years) were randomized into two groups: the placebo group and the functional beverage group (the test group). Functional beverage was composed of 2000 mg soy peptide, 20 mg L-carnitine and 300 mg garcinia(40% hydroxycitric acid). Body weight and 3 day food dimes, biochemical measurements and computerized tomography were measured at baseline and 8-week. After 8-week consumption of functional beverage with usual diet and exercise, body weight fell an average of 1.4 kg (2.1%). Visceral fat area reduced an average of 7.8% at L1($69.6{\pm}8.7\;vs\;64.2{\pm}7.5\;\textrm{cm}^2$) and 5.1% ($60.7{\pm}4.9\;vs\;57.6{\pm}4.8\;\textrm{cm}^2$, p<0.05) at L4level after weight loss in the test group. Calf fat area in the test group showed about 10% reduction ($31.0{\pm}2.7\;vs=\;27.7{\pm}1.7\;\textrm{cm}^2$, p<0.05) after weight loss. These reductions in fat areas were not shown in the placebo group. There were tendencies of increase in serum levels of $\beta-hydroxybutyrate$, acetoacetate, and total ketones in the test group. There were 7% and 17% insignificant increase in fasting free fatty acid (FFA) and response area of FFA during oral glucose tolerance test(OGTT), respectively, in this group. ill addition, little weight loss in the test group showed 8% but not significant reduction in insulin response area during OGTT. In conclusion, this study shows that taking a mixture of carnitine, hydroxycitric acid, and soy peptide as a potential anti-obesity supplement for 8-week produced advantageous changes in the weight and visceral fat accumulation of overweight women.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.253-275
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• 1994

Many flowering plants possess genetically controlled self -incompatibility (SI) system that prevents inbreeding and promotes outcrosses. SI is usually controlled by a single, multiallelic S-locus. In gametophytically controlled system, SI results when the S-allele of the pollen is matched by one of the two S-alleles in the style, while in the sporophytic system self-incompatible reaction occurs by the interaction between the pistil genotype and genotype of, not the pollen, but the pollen parent In the former system the self-incompatible phenotype of pollen is determined by the haploid genome of the pollen itself but in the latter the pollen phenotype is governed by the genotype of the pollen parent along with the occurrence of either to-dominant or dominant/recessive allelic interactions. In the sporophytic type the inhibition reaction occurs within minutes following pollen-stigma contact, the incompatible pollen grains usually failing to germinate, whereas in gametophytic system pollen tube inhibition takes place during growth in the transmitting tissue of the style. Recognition and rejection of self pollen are the result of interaction between the S-locus protein in the pistil and the pollen protein. In the gametophytic SI the S-associated glycoprotein which is similar to the fungal ribonuclease in structure and function are localized at the intercellular matrix in the transmitting tissue of the style, with the highest concentration in the collar of the stigma, while in the sporophytic SI deposit of abundant S-locus specific glycoprotein (SLSG).is detected in the cell wall of stigmatic papillae of the open flowers. In the gametophytic system S-gene is expressed mostly at the stigmatic collar the upper third of the style length and in the pollen after meiosis. On the other hand, in the sporophytic SI S-glycoprotein gene is expressed in the papillar cells of the stigma as well as in e sporophytic tape is cells of anther wall. Recognition and rejection of self pollen in the gametophytic type is the reaction between the ribonuclease in the transmitting tissue of the style and the protein in the cytoplasm of pollen tube, whereas in the sporophytic system the inhibition of selfed pollen is caused by the interaction between the Sycoprotein in the wall of stigmatic papillar cell and the tapetum-origin protein deposited on the outer wall of the pollen grain. The claim that the S-allele-associated proteins are involved in recognition and rejection of self pollen has been made merely based on indirect evidence. Recently it has been verified that inhibition of synthesis of S$_3$ protein in Petunia inflata plants of S$_2$S$_3$ genotype by the antisense S$_3$ gene resulted in failure of the transgenic plant to reject S$_3$ pollen and that expression of the transgenic encoding S$_3$ protein in the S$_1$S$_2$ genotype confers on the transgenic plant the ability to reject S$_3$ pollen. These finding Provide direct evidence that S-proteins control the s elf-incompatibility behavior of the pistil.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.06a
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• pp.67-86
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• 2001

A strain producing strongly fibrinolytic enzyme was isolated from soil and was identified to be Bacillus subtilis by biochemical and physiological characterization. The optimal culture conditions for the production of fibrinolytic enzyme was determined to be 1.0% tryptone, 1.5% soluble starch, 0.5% Peptone, 0.5% NaCl, $(NH_{4})_{3}PO_4.3H_{2}O, and MgSO_{4}.7H_{2}O.$ Initial pH and temperature were pH 8.0 and $30^{\circ}C$ , respectively, The highest enzyme production was observed at 30 hours of cultivation at $30^{\circ}C$ The fibrinolytic enzyme was purified to homogeneity by DEAE Sephadex A-50 ion exchange column chromatography, 70% ammonium sulfate precipitation, Sephadex G-200 and G-75 gel filtration column chromatography. The molecular weight of the purified enzyme was 28,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A gene encoding the fibrinolytic enzyme was cloned into a plasmid vector pBluescript, transforming E.coli XL-1 Blue. The clone was able to degrade fibrin, This indicated that the gene could encode a fibrinolytic enzyme. The nucleotide sequence of the 2.7 kb insert was determined in both direction. One open reading frame composed of 1023 nucleotides was found to be a potential protein coding region. There was the putative Shine-Dalgano sequence and TATA box upstream of the open reading frame. The homology search data in the genome database showed that both the 2.7 kb insert and 1 kb open reading frame carried no significance in the nucleotide sequence of known fibrinolytic enzyme from Bacillus serovars. The recombinant cell harboring the novel gene involved in fibrinolysis was subjected to protein purification. The molecular mass of the purified fibrinolytic enzyme was determined to be 31864 Dalton, which was highly in accordance with the molecular mass(33 kDa) of the fibrinolytic gene deduced from the insert. The fibrinolytic enzyme was Purified 50.5 folds to homogeneity in overall yield of 10.7% by DEAE Sephadex A-50 ion exchange, 85% ammonium sulfate precipitation, Sephadex G-50, Superdex 75 HR FPLC gel filtration. In conclusion, a novel fibrinolytic gene from Bacillus subtilis was identified and characterized by cloning a genomic library of Bacillus subtilis into pBleuscript. For the soybean fermented by this strain, it is found that there increased assistant protein about 20% compared to the soybean not fermented and increased about 30% according to amino acid analysis and, in particular, essential amino acid increased about 40%. When keeping this fermented soybean powder at room temperature for about 70days, it showed very high stability maintaining almost perfect activity and, therefore, it gave us great suggestion its possibility of development as a new functional food.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.723-727
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• 2007

Resistance to metronidazole in Helicobacter pylori results from inactivation of rdxA and frxA, the chromosomal genes for a nitroreductase that normally converts metronidazole from prodrug to bactericidal agent. Two types of metronidazole susceptible strains had been found distinguishable by their apparent levels of frxA expression. Most common in the populations we had studied were strains that required only rdxA inactivation to become resistant to moderate levels of metronidazole(type I strains). The second strain type required inactivation of both frxA and rdxA to become resistance to metronidazole(type II strains): this was linked to a relatively high level of frxA gene transcription in the type II strains. The fdxA gene regulated fdxA as well as rdxA gene. Thus, to study the function of fdxA as a regulatory gene we constructed a null mutant of fdxA in H. pylori genome and identified over-and under-expressed proteins by fdxA using two-dimensional(2-D) electrophoresis and MALDI-TOP-MS. There were four over-expressed proteins in fdxA mutant; nifU-like protein(HP0221), frxA(HP0642), nonheme ferritin(HP0653), and hypothetical protein(HP0902). Three under-expressed proteins were also identified in fdxA mutant, including 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase (HP0089), (3R)-hydroxymyristoyl ACP dehydratase(HP1376), and thioredoxin(HP1458).

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.402-406
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• 2007

This study was performed to develop the molecular marker for sex determination of hare (Lepus coreanus) distributed in Korea which focused on sexual dimorphism between X and Y chromosomal homologous genes, zinc finger-X (ZFX) and -Y (ZFY). The intron 7 regions of ZFX and ZFY genes exhibited differential amplification patterns between male and female hares. The lengths of intron 7 region of ZFX and ZFY genes were 538 and 233-bp, respectively. Especially, the ZFX intron 7 contained a repetitive sequence identified as member of RNA-mediated transposable elements which was similar to CSINE2 commonly found in the rabbit genome. However, it was not present in intron 7 of ZFY gene. The molecular sex typing by polymerase chain reaction (PCR) was also carried out to determine the sex of hare based on difference in lengths between the intron 7 regions of ZFX and ZFY genes. All DNA samples tested had common band amplified from ZFX. However, the male hare DNAs had two distinct bands which amplified from ZFX and ZFY genes, respectively. The results from ZFX-ZFY PCR sex typing were identical to those from phenotypic investigation and from amplification patterns using male-specific sex determining region Y (SRY) gene as well. Finally, this study suggested that the sexual dimorphism between intron 7 regions of ZFX and ZFY could be useful genetic marker to determine sex of hare.

• Journal of Life Science
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• v.23 no.2
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• pp.273-281
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• 2013

The purpose of this research was to investigate the production and characterization of alkaline protease from Micrococcus sp. PS-1 newly isolated from seawater. Micrococcus sp. PS-1 was grown in Luria-Bertani (LB) medium. Its optimal temperature and pH for growth were $30^{\circ}C$ and 7.0, respectively. The effect of nitrogen sources was investigated on optimal enzyme production. A high level of alkaline protease production occurred in LB broth containing 2% skimmed milk. The protease was purified in a 3-step procedure involving ultrafiltration, acetone precipitation, and dialysis. The procedure yielded a 16.43-purification fold, with a yield of 54.25%. SDS-PAGE showed that the enzyme had molecular weights of 35.0 and 37.5 kDa. Its maximum protease activity was exhibited at pH 9.0 and $37^{\circ}C$, and its activity was stable at pH 8.0-11.0 and $25-37^{\circ}C$. The protease activity was strongly inhibited by PMSF, EDTA, and EGTA. Taken together, the results demonstrate that the protease enzyme from Micrococcus sp. PS-1 probably belongs to a subclass of alkaline metallo-serine proteases.