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To enhance the production efficiency of foreign protein in baculovirus expression systems, the effects of polyhedrin fragments were investigated by fusion expressing them with the enhanced green fluorescent protein (EGFP). Recombinant viruses were generated to express EGFP fused with polyhedrin fragments based on the previously reported minimal region for self-assembly and the KRKK nuclear localization signal (NLS). Fusion expressions with polyhedrin amino acids 19 to 110 and 32 to 110 lead to localization of recombinant protein into the nucleus and mediate its assembly. The marked increase of EGFP by these fusion expressions was confirmed through protein and fluorescence intensity analyses. The importance of nuclear localization for enhanced production was shown by the mutation of the NLS within the fused polyhedrin fragment. In addition, when the polyhedrin fragment fused with EGFP was not localized in the nucleus, some fragments increased the production of protein. Among these fragments, some degradation of only the fused polyhedrin was observed in the fusion of amino acids 19 to 85 and 32 to 85. The fusion of amino acids 32 to 85 may be more useful for the enhanced and intact production of recombinant protein. The production of E2 protein, which is a major antigen of classical swine fever virus, was dramatically increased by fusion expression with polyhedrin amino acids 19 to 110, and its preliminary immunogenicity was verified using experimental guinea pigs. This study suggests a new option for higher expression of useful foreign recombinant protein by using the partial polyhedrin in baculovirus.

Monochamus saltuarius is a vector for pine wilt disease that causes enormous damage to native pine trees in Korea. To develop a biological control method for this pine wilt disease vector, an entomopathogenic fungus was isolated from the cadaver of an adult M. saltuarius supporting fungal conidiation. This fungus was named MsW1 and identified as Beauveria bassiana by microscopic examination, PCR amplification using B. bassiana -specific primers and genetic sequencing of the ITS and EF1-α regions. Virulence tests against M. saltuarius were conducted with conidial suspensions (1 × 10(8) conidia/ml) of B. bassiana MsW1 in laboratory conditions. The median lethal times (LT(50)) of adults and larvae were 7.2 and 7 days, and 100% mortality was observed at 11 and 13 days after inoculation, respectively. This is the first characterization of B. bassiana from M. saltuarius.

Mamestra brassicae nucleopolyhedrovirus-K1 (MabrNPV-K1) was isolated from naturally infected M. brassicae (Lepidoptera: Noctuidae) larvae in Korea. The full genome sequences of MabrNPV-K1 were determined, analysed and compared to those of other baculoviruses. The MabrNPV-K1 genome consisted of 152,710 bp and had an overall G + C content of 39.9%. Computer-assisted analysis predicted 158 open reading frames (ORFs) of 150 nucleotides or greater that showed minimal overlap. Two inhibitor of apoptosis (iap) and six baculovirus repeated ORFs were interspersed in the MabrNPV-K1 genome. The unique MabrNPV-K1 ORF133 was identified in the MabrNPV-K1 genome that was not previously reported in baculoviruses. The gene content and arrangement in MabrNPV-K1 had the highest similarity with those of Helicoverpa armigera MNPV (HearMNPV) and Mamestra configurata NPV-B (MacoNPV-B), and their shared homologous genes were 99% collinear. The MabrNPV-K1 genome contained four homologous repeat regions (hr1, hr2, hr3 and hr4) that accounted for 3.3% of the genome. The genomic positions of the four MabrNPV-K1 hr regions were conserved among those of HearMNPV and MacoNPV-B. The gene parity plot, percent identity of the gene homologues and a phylogenetic analysis suggested that these three viruses are closely related not only to each other but also to the same virus strains rather than different virus species.

The cladoceran Daphniamagna has been used as an aquatic test species in aquatic toxicology. To evaluate the aquatic toxicity of leachate from concrete, the immobilization of D. magna was observed after treatment of various concentrations of leachate specimens. Reliabilities of the culture condition and the experimental protocol for acute toxicity test were successfully achieved from the standard toxicity test. The leachates were prepared from the mixture of Ordinary Portland Cement (OPC) and pozzolanic admixtures, Pulverised fuel ash (PFA), Ground granulated blast furnace slag (GGBS) and GGBS containing loess. Acute toxicity test showed 100% immobilization of D. magna for OPC or PFA. The leachates from OPC or PFA had high pH 10 to 12. However, GGBS and GGBS containing loess showed less toxicity according to the concentrations. Especially, immobilization was not observed at the concentrations below 12.5% of GGBS containing loess. Also the range of pH for these specimens was 8 to 9. This suggested that the use of loess as the admixture in concrete may be useful to reduce eco-toxicity of leachates from concrete. This our study provided the harmfulness of the alkali leaching from concrete in aquatic environment and the usefulness of D. magna to evaluate the toxicity of leachates from concrete. IntroductionThe detection and presence of toxic materials in environment is one of the most popular interests because of their harmful effects on ecosystem including human. Especially, the presence of toxic materials in aquatic environment is more considerable to evaluate the harmfulness. The evaluation of contamination in aquatic environment has been for a long time performed only by specific chemical analyses, but many experiences and studies have shown the inadequacy of such approach. To complement this chemical analysis, the biological methods using fish or algae have been used to evaluate and monitor the water quality for many years (Sandbacka et al., 2000;Versteeg et al., 1997 component, but its assessment for environment has not been studied yet. The alkali leaching is not only problem to architectural structures but also more serious to the construction of bridges, dams and other offshore structures (Van Gerven et al., 2007;Mohamed and El Gamal, 2011). The purpose of this study, therefore, was to evaluate the usage of eco-toxicity assays with D. magna in water contaminated with alkali leaching of concrete. To reduce toxicity, in additionally, the effect of loess as the eco-friend admixture was evaluated. Materials and Methods Culturing of D. magnaDaphniamagna was obtained from Korea Envicladoceran Daphniamagna Straus has been used as a "standard" aquatic test species among cladoceran and most frequently used for chronic and acute tests in aquatic toxicology (ASTM, 1987; EEC, 1992;OECD, 1992). Many countries are using aquatic toxicity tests as part of their water quality monitoring program (Slabbert and Venter, 1999). In Korea also, the D. magna has been used for the assessment of toxicity in aquatic environment from 2...

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The greenhouse whitefly, Trialeurodes vaporariorum, is an economically important pest for greenhouse crops because they cause direct damage by feeding on plant nutrients and indirect damage as transmits many virus vectors. It has recently become a serious problem because of the continuous use of insecticide resulting in resistance among greenhouse whitefly population. To overcome these problems, in this study, the biological characteristics and virulence of an entomopathogenic fungus isolated from the cadaver of nymph greenhouse whitefly were investigated. Isolated fungus was identified as Isaria fumosorosea by morphological examinations and genetic identification using sequences of the ITS, β-tubulin, and EF1-α regions. This fungus was named as I. fumosorosea SDTv and tested for the virulence against nymphs T. vaporariorum and the cold activity, the thermotolerance and the stability of UV-B irradiation on conidia. Mortality rate of greenhouse whitefly showed from 84 to 100% and the virulence increased with increasing conidial concentrations, 1×10 5 to 10 8 conidia/ml. Conidia were stable at 35℃, 0.1 J/cm 2 of UV irradiation and germinated after 8 days at 4℃. Additionally, the activities of chitinases and proteases produced by I. fumosorosea SDTv were varied according to the medium. In conclusion, I. fumosorosea SDTv which showed high mortality rate against greenhouse whitefly will be used effectively in the integrated pest management programs against the greenhouse whitefly.