• Journal of Life Science
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• v.8 no.2
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• pp.216-225
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• 1998

Metal ion-induced and it’s regulatory genes were screened in virulent salmonella typhimurium UK1 and tested cross-regulation with various stresses. Using the techniqud of P22-MudJ(Km, lacZ)-directed lacZ operon fusion, LF40 cuiA::MudJ and Lf153 cuiD::MudJ which were induced by copper were selected. cuia and cuiD were determined anaerobic coper inducible and copper tolerance response gene, respectively. Also cuiA and cuiD locus were determined at 81 and 8min, respectively, on salmonella Genetic Map. The two regulators were identified as cuaR, and cudR, which controls cuiA and cuiD, respectively. cuaR, and cudR appeared as negative regulators because the expression of cuiA-lac-Z and cuiD-lacZ were increased. Copper adapted UK1 showed high resistance to H$_{2}$O$_{2}$, but cuiD did not. The product of the cudR locus was responsible for decreasing the tolerance to copper and H$_{2}$O$_{2}$. Furthemore cuiA and cuiD locus were found to be part of a regulon under the control of a trans-acting regulators, rpoS, oxyR and relA. Therefore, the results suggest CTR participate with oxidative stress on Salmonella.

• BMB Reports
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• v.43 no.12
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• pp.789-794
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• 2010

A novel gene, designated mgt-6, containing four splicing variants, was isolated from a gene trap clone library of C3H/10T1/2 cells transfected with retroviral promoterless gene-trap vector, ROSAFARY. The transcript variants were differentially expressed in murine tissues and cell lines and differentially responded to diverse stimuli including TGF-${\beta}1$ and mitogen-activated protein kinase (MAPK) inhibitors. The mgt-6 gene encoded a protein of 37 or 11 amino acid residuals with cytoplasmic distribution. However, when C3H/10T1/2 cells were treated with 5-azacytidine, the protein translocated into cell nucleus as indicated by fused LacZ or C-terminally tagged EGFP. Our preliminary results suggest that further study on the role of mgt-6 gene in cell transformation and differentiation may be of significance.

• Journal of Life Science
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• v.9 no.2
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• pp.169-175
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• 1999

Salmonella typhimurium can encounter a wide variety of environments during its life cycle. In nature, S. typhimurium can experience and survive dramatic acid stresses that occur in diverse ecological niches ranging from pond water to phagolysosomes. These survival mechanism is aquired by the Acid Tolerance Response(ATR) in Salmonella. The ATR of S. typhimurium is a complex inducible phenomenon in which exposures to slight or moderate low pH will produce a stress response capable of protecting the organism against more severe acid challenges. ATR in Salmonella has two different systems that are called RpoS dependent and independent. We found that ATR in anaerobic was showed RpoS independent because rpoS$\Omega$AP had ATR as S. typhimurium UK1. Using the P22 MudJ(Km, lacZ) operon fusion technique and a lethal selection procedure combining low pH(pH4.5) and sodium acetate(10mM, pH4.5), we isolated LF487 aatA::MudJ which showed acid sensitive in anaerobic condition. aatA locus was determined at 12 min on Salmonella Genetic Map. The survival rate of aatA mutant was showed significantly diminished at pH4.3 than virulent wild type Salmonella in anaerobic condition(5% $CO_2$, 5% H$_2$, 90% $N_2$). Therefore isolated gene was confirmed important gene for anaerobic ATR system.

• The Journal of Natural Sciences
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• v.5 no.1
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• pp.37-45
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• 1992

The gene coding for $\beta$-galactosidase of Neisseria lactamica 2118 was cloned into Escherichia coli MC 1061. The isolated 6.5 Kb EcoR I fragement and 7.2 Kb BamH I fragment of chromosomal DNA in Southern hybridization were ligated to a vector plasmid pBR322 and then transformed into Escherichia coli MC 1061 cells. Finally, I obtained three clones as $\beta$-galactosidase positive clone by colony hybridization and Southern hybridization($\beta$-galactosidase probe: lac Z gene of pMC1871). Three recombinant plasmids(pNL.13. 17 and 24) were found to contain the 7.2Kb BamH I fragment originated from Neisseria lactamica 2118 chromosomal DNA by Southern hybridization and pNL 24 was showed high homology to probe especially and also its physical map was constructed.

• Journal of Microbiology
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• v.33 no.2
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• pp.120-125
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• 1995

.betha.-galactosidase activity of Escherichia coli cells containing operon fusion nhaA'-'lacZ was monitored to study the regulation of expression of nhaA gene under various conditions. The expression of the fusion was enhanced only by chemicals containing Na$^{+}$ or Li$^{+}$. This Na$^{+}$ or Li$^{+}$. This Na$^{+}$(Li$^{+}$)-specific enhancement of .betha.-galactosidase activity represented the increase in the rate of synthesis of .betha.-galactosidase rather than the decrease in the breakdown rate. The induction pattern was influenced by copy numbers of the gene. Induction by Na$^{+}$ or Li$^{+}$ was concentration and time dependent, reaching maximum 5-6 fold induction after 2 hours at 0.4-0.5 M for Na$^{+}$ or at 0.25-0.35 M for Li$^{+}$, Although the expression was induced at much lower concentration of Na$^{+}$ at alkaline pH values than at neutral pH in the presence of Na$^{+}$, alkaline pH itself did ot induced the expression of the fusion in the absence of Na$^{+}$. Temperature shift and growth phase of culture did not affect the level of induction.he level of induction.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1635-1640
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• 2004

Two experiments were conducted to evaluate developmental gene expression of antimicrobial peptide PR-39 and effect of zinc oxide on gene regulation of PR-39 in piglets using semi-quantitative RT-PCR analysis. In experiment 1, fifteen female Tai-Hu pigs (a local breed in China) in five groups, each of three pigs at 1, 14, 28, 42 and 56 days of age were used to determine effect of age and weaning on mRNA expression of PR-39. In experiment 2, nine groups of pigs (total seventy-two female 36 days-age weanling Tai-Hu piglets) were assigned to three treatments (${ZnO}_0$, ${ZnO}_{100}$ and ${ZnO}_{3000}$). The feeding experimental period lasted 15 days. After feeding experiment, nine pigs with three animals in each treatment were chosen to determine the effect of ZnO on PR-39 mRNA expression of pigs. The results showed that PR-39 mRNA levels increased steadily in postnatal day 1-28 (preweaning), and weaning significantly decreased PR-39 mRNA expression of piglets (p<0.05). ${ZnO}_{3000}$ (3,000 mg zinc/kg diet) significantly increased PR-39 mRNA expression (p<0.05) when piglets were feed ${ZnO}_{3000}$ diet for 15 days. ${ZnO}_{100}$ (100 mg zinc/kg diet) also increased PR-39 gene expression, but the result was not statistically significant (p>0.05). The result was in accordance with the effect of ${ZnO}_{3000}$ and ${ZnO}_{100}$ on weight gain of piglets and prevention of diarrhea.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.521.3-522
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• 1986

A gene encoding alcohol dehydrogenase (ADH) in Zymomonas mobilis was cloned into E. coli JM 83 with plasmid pUC 9. The ADH produced by the E. coli transformant was purified bysonication, (NH$^4$)2SO4 fractionation, Affi-Gel blue and hydroxylapatite chromatography. The ADH produced by Z. mobilis was also purified by the same procedures. The two enzyme preparations were characterized and compared. It was found that the E. coli ADH was identical to one of two ADH isozymes of Z. mobilis. Analytical gel filtrations led to the conclusion that the molecule of E. coli ADH was composedv of four subunits having molecular weight of 40,000 (+1,000) dalton each The effect of metal ions on ADH activity and optimum pH were investigated.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.465-470
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• 2009

The chicken Mx gene has been regarded as a candidate gene for resistance to avian influenza virus (AIV). In this study, three groups of chickens with homozygotes (AA, GG) and heterozygotes (AG) of the resistant (A) and susceptible alleles (G) to AIV of the Mx gene were constructed from a line of dwarf egg-type chickens. These chickens were not examined for their resistant activities to AIV because the differential resistance had only been detected in vitro. The birds of the three groups were vaccinated with inactivated H5N2 AIV vaccine and the level of hemagglutination inhibition (HI) antibody to AIV was detected. The association between disease resistant activity to AIV and antibody response to AIV vaccination in the three groups was analyzed. The chickens with homozygous resistant allele A showed the lowest antibody levels, whereas the heterozygous chickens (AG) presented the highest antibody level after the boosting vaccination, which indicates that the efficiency of artificial selection on the resistant allele of Mx gene will be compromised since the homozygotes of the allele presented the weakest antibody response to the corresponding vaccine.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.389-397
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• 2002

Bacteriocin-producing lactic acid bacteria were isolated from kimchi. One isolate producing the most efficient bacteriocin was identified and named Lactococcus lactis B2, based on the biochemical properties and 16S rDNA sequences. The B2 bacteriocin inhibited many different Gram positive bacteria including Lactococcus, Lactobacillus, Leuconostoc, Enterococcus, Streptococcus, and Staphylococcus, but did not inhibit Gram-negative bacteria. The bacteriocin was maximally produced at temperatures between $25^{\circ}C\;and\;30^{\circ}C$ and at the initial pH of 7.0. Ninety $\%$ of the activity remained after 10 min of heat treatment at $121^{\circ}C,\;and\;100\%$, after 1 h exposure to organic solvents. The bacteriocin was purified from culture supernatant by ammonium sulfate precipitation, CM Sepharose column chromatography, ultrafiltration, and finally, by reverse-phase HPLC. A 1.58-kb fragment was amplified from B2 chromosome by using a primer set designed from the published nisA sequence. Sequencing result showed that the fragment contained the whole nisZ and 5' portion of nisB, whose gene product was involved in postmodification of nisin. The upstream sequence, however, was completely different from those of reported nisin genes.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.105-110
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• 1998

The baculovirus egt gene encodes an ecdysteroid UDP-glucosyltransferase(EGT) which catalyzes the transfer of glucose from UDP-glucose to the insect moltion hormone ecdysteroid resulting in a functionally inactive ecdysteroid. In baculovirus-infected insect larvae, EGT has been shown block molting and pupation. In this study, we compared the development of 4th and 5th instar silkworm, Bombyx mori, larvae injected with either wild-type bombyx mori nucleopolyhedrovirus (BmNPV) or a mutant BmNPV(BmEGTZ) in which the egt gene was disrupted by the insertion of a lacZ gene cassette. Larvae injected with BmEGTZ died roughly 12 h more rapidly compared to indentical larvae infected with BmNPV. In addition, BmEGTZ- infected larvae prematurely stopped feeding and gain less weight compared to BmNPV-infected larvae. In order to investigate why BmEGTZ-infected larvae died more rapidly than BmNPV-infected larvae, the array of hemolymph proteins in BmEGTZ-or BmNPV-infected larvae were analyzed by SDS-PAGE. The hemolymph of BmEGTZ-infected larvae showed virus-specific proteins, including polyhedrin, about 12 h earlier than the hemolymph of BmNPV-infected larvae