• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.562-567
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• 1999

Single-stranded DNA binding protein (SSB) is well-characterized as having a helix-destabilizing activity. The helix-destabilizing capability of SSB has been re-examined in this study. The results of restriction endonuclease protection assays and titration experiments suggest that the stimulatory effect of SSB on strand exchange acts by melting out the secondary structure which is inaccessible to RecA protein binding; however, SSB is excluded from regions of secondary structure present in native single-stranded DNA. Complexes of SSB and RecA protein are required for eliminating the secondary structure barriers under optimal conditions for strand exchange.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.121-128
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• 1986

The biochemical properties of ribonucleic acid (RNA) and coat protein of the mild tobacco mosaic virus (TMV) mutant, Tw 333 are described. The molecular weight of the RNA calculated from polyacrylamide gel electrophoresis was $2.03\times10^6$ daltons. The molar ratio of the bases of the RNA was 25.4 guanine, 29.2 adenine, 17.5 cytosine and 27.9 uracil in moles. The hyperchromicity on Tw 333-RNA by thermal denaturation was $25.1\%$, indicating Tm value of $47^{\circ}C$. The virus coat protein migrated as a single component in SDS-polyacrylamide gel electrophoresis and had a molecular weight of 17,500 daltons. A total of 158 amino acid residues are present in the protein. Separation of the tryptic peptides by electrophoresis and chromatography yielded ninhydrin-positive compounds. The biochemical properties of RNA and coat protein of the mild mutant we very similar to those of wild type of TMV-OM strain, but some difference between the strains were observe in the base composition, hyperchromicity, amino acid composition and tryptic peptide map.

• BMB Reports
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• v.38 no.4
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• pp.447-456
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• 2005

TNF-$\alpha$ plays a pivotal role in inflammation processes which are mainly regulated by endothelial cells. While TNF-$\alpha$ induces apoptosis of several cell types like tumor cells, endothelial cells are resistant to TNFa mediated cell death. The cytotoxic effects of TNF-$\alpha$ on most cells are only evident if RNA or protein synthesis is inhibited, suggesting that de novo RNA or protein synthesis protect cells from TNF-$\alpha$ cytotoxicity, presumably by NF-${\kappa}B$ mediated induction of protective genes. However, the cytoprotective genes involved in NF-${\kappa}B$ dependent endothelial cell survival have not been sufficiently identified. In the present study, the suppression subtractive hybridization (SSH) method was employed to identify rarely transcribed TNF-$\alpha$ inducible genes in human arterial endothelial cells related to cell survival and cell cycle. The TNF-$\alpha$-induced expression of the RNA binding protein $p54^{nrb}$ and the 14-3-3 protein HS1 as shown here for the first time may contribute to the TNF-$\alpha$ mediated cell protection of endothelial cells. These genes have been shown to play pivotal roles in cell survival and cell cycle control in different experimental settings. The concerted expression of these genes together with other genes related to cell protection and cell cycle like DnaJ, $p21^{cip1}$ and the ubiquitin activating enzyme E1 demonstrates the identification of new genes in the context of TNF-$\alpha$ induced gene expression patterns mediating the prosurvival effect of TNF-$\alpha$ in endothelial cells.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.2
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• pp.123-129
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• 2000

Expression of the crylAcl gene of an acrystalliferous Bacillus thuringiensis strain under the control of the native or $\alpha$-amylase gene promoter was investigated. The crylAcl gene was cloned in a B. thuringiensis - E. coli shutle vector, pHT3101, undder the control of either the native promoter (pProAc) or the $\alpha$-amylase promoter from Bacillus subtilis (pAmyAc). These two recombinant plasmids were successfully expressed in B. thuringiensis subsp. kurstaki Cry B. The first transformant (ProAc/CB), harboring pProAc, expressed an about 130 kDa protein begining 24 hr after inoculations just as in the case of the wild type of B. thuringiensis subsp. kurstaki HD-73. The second pAmyAc-transformant (AmyAc/CB) began to express the gene just 6 hr after inoculation, but Western analysis showed that the activity of the $\alpha$-amylase promoter was relatively weaker than that of the native promoter. As expected, their toxicity against Plutella xylostella larvae was dependent on the amount of Cry1Acl protein expressed.

• KSBB Journal
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• v.17 no.3
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• pp.283-289
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• 2002

The present study was aimed at investigating the metabolic regulation of insulin-like growth factor-I(IGF-I) expression in fasting animals. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA from control, 4d-fasting, and 2d-fasting-refed rats. The levels of IGF-I transcripts were reduced in 4d-fasting than in control by decreasing its transcriptional rate, which was measured through nuclear nun-on assay. DNase I footprinting, which was performed using nuclear extracts from fasting rat, demonstrated protein binding to a sequence that extended from +179 to +210 (termed region B). These data suggest that the expression of IGF-I is transcriptionally regulated through DNA-liver enriched protein binding in a sequence which is located downstream from major transcription initiation site of IGF-I gene.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1173-1181
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• 2016

Salmonella spp. are gram-negative flagellated bacteria that cause a variety of diseases in humans and animals, ranging from mild gastroenteritis to severe systemic infection. To explore development of a potent vaccine against Salmonella infections, the gene encoding outer membrane protein L (ompL) was inserted into the swinepox virus (SPV) genome by homologous recombination. PCR, western blot, and immunofluorescence assays were used to verify the recombinant swinepox virus rSPV-OmpL. The immune responses and protection efficacy of rSPV-OmpL were assessed in a mouse model. Forty mice were assigned to four groups, which were immunized with rSPV-OmpL, inactive Salmonella (positive control), wild-type SPV (wtSPV; negative control), or PBS (challenge control), respectively. The OmpL-specific antibody in the rSPV-OmpL-immunized group increased dramatically and continuously over time post-vaccination, and was present at a significantly higher level than in the positive control group (p < 0.05). The concentrations of IFN-γ and IL-4, which represent Th1-type and Th2-type cytokine responses, were significantly higher (p < 0.05) in the rSPV-OmpL-vaccinated group than in the other three groups. After intraperitoneal challenge with a lethal dose of Salmonella typhimurium CVCC542, eight out of ten mice in the rSPV-OmpL-vaccinated group were protected, whereas all the mice in the negative control and challenge control groups died within 3 days. Passive immune protection assays showed that hyperimmune sera against OmpL could provide mice with effective protection against challenge from S. typhimurium. The recombinant swinepox virus rSPV-OmpL might serve as a promising vaccine against Salmonella infection.

• Korean journal of applied entomology
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• v.21 no.1 s.50
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• pp.23-26
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• 1982

The present study was carried out to investigate the change of peroxidase activity of soybean seed infected with Cerrospora kikurhii. The protein content, polyphenol oxidase activity and peroxidase isozyme pattern in health and infected soybean seed were also compared. 1. The peroxidase activity was substantially higher in the infected soybean seeds than that in the healthy seeds either cracked or not. No significant differences in protein content were recognized among the seeds tested. 2. No significant differences in peroxidase activities and protein contents were notified between healthy and infected seeds from the measurements on each parts of dissected seeds, cotyledon and seedcoat, however the peroxidase activity in the seed coat of the stained seed was 2.5 times to healthy seed. 3. The activities of polyphenel oxidase were undectable in both healthy and diseased seeds. 4. The electrophoretic Patterns of the Peroridase isozyme were the same between healthy and in footed seed. 5. Therefore, the increase of peroxidase activity in infected soybean seedcoat was mainly due to the biochemical reaction against the pathogen.

• Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.149-158
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• 2013

We demonstrate enhanced growth, innate immunity and protection against hydrogen peroxide ($H_2O_2$)-induced protein oxidation and cellular DNA damage in olive flounder Paralichthys olivaceus fed a chitosan-coated moist pallet (MP) diet. A chitosan-based biopolymer coated MP as the experimental diet and a non-coated MP (control) was fed to olive flounder fish. Growth, including the average weight gain (g/fish), weight gain (%) and feed intake (g) of the fish group fed a chitosan-coated MP diet increased significantly. The survival rate was reported as 100% throughout the experimental period. Immunological parameters indicated higher mucus lysozyme activity and significantly higher fish skin mucus total protein content was observed in fish fed the chitosan-coated MP diet compared to the control. A blood plasma analysis revealed attenuation of cellular DNA and protein oxidative damage caused by $H_2O_2$-induced oxidative stress in the fish fed the chitosan-coated MP diet compared to the control group. Moreover, blood serum biochemical analysis revealed health-promoting effects, including significantly higher hemoglobin and total cholesterol levels in the fish fed the chitosan-coated MP diet compared to the control group. In conclusion, growth, innate immunity and protection against oxidative stresses were improved by feeding of the chitosan-coated MP diet to olive flounder reared in aquaculture.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.161-166
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• 2019

This study was done to characterize distribution of Rickettsia spp. in ticks in the northwestern and southwestern provinces in the Republic of Korea. A total of 2,814 ticks were collected between May and September 2009. After pooling, 284 tick DNA samples were screened for a gene of Rickettsia-specific 17-kDa protein using nested PCR (nPCR), and produced 88 nPCR positive samples. Of these positives, 75% contained 190-kDa outer membrane protein gene (ompA), 50% 120-kDa outer membrane protein gene (ompB), and 64.7% gene D (sca4). The nPCR products of ompA, ompB, and sca4 genes revealed close relatedness to Rickettsia japonica, R. heilongjiangensis, and R. monacensis. Most Rickettsia species were detected in Haemaphysalis longicornis. This tick was found a dominant vector of rickettsiae in the study regions in the Republic of Korea.

• Parasites, Hosts and Diseases
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• v.56 no.5
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• pp.429-435
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• 2018

Toxoplasma gondii is a ubiquitous protozoan parasite responsible for causing toxoplasmosis. Preventive measures for toxoplasmosis are currently lacking and as such, development of novel vaccines are of urgent need. In this study, we generated 2 virus-like particles (VLPs) vaccines expressing T. gondii rhoptry protein 4 (ROP4) or rhoptry protein 18 (ROP18) using influenza matrix protein (M1) as a core protein. Mice were intranasally immunized with VLPs vaccines and after the last immunization, mice were challenged with ME49 cysts. Protective efficacy was assessed and compared by determining serum antibody responses, body weight changes and the reduction of cyst counts in the brain. ROP18 VLPs-immunized mice induced greater levels of IgG and IgA antibody responses than those immunized with ROP4 VLPs. ROP18 VLPs immunization significantly reduced body weight loss and the number of brain cysts in mice compared to ROP4 VLPs post-challenge. These results indicate that T. gondii ROP18 VLPs elicited better protective efficacy than ROP4 VLPs, providing important insight into vaccine design strategy.