• Korean journal of applied entomology
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• v.36 no.4
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• pp.341-350
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• 1997

We have now constructed a novel recombinant baculovirus producing fusion protein with Autographa californica nuclear polyhedrosis virus (AcNPV) polyhedrin and Bacillus thuringiensis(Bt) cryIA(c) crystal protein. The fusion protein expressed by the recombinant baculovirus in insect cells was characterized. The N-terminal of cryIA(c) gene of Bt subsp. kurstaki HD-73 was introduced under the control of polyhedrin gene promoter of AcNPV, by fusion in the front of intact polyhedrin gene or by insertion into the HindIII site in polyhedrin gene. The recombinant baculoviruses were named as BtrusI or BtrusII, respectively. Although single transcript from the fusion protein gene was apparently observed. BtrusI was produced the two proteins, 92 kDa fusion protein and only polyhedrin. In addition, fusion protein produced by BtrusI did not form polyhedra. Interestingly, however, the cells infected with BtrusII did not show a 33 kDa polyhedrin band as a cells infected with BtrusI. Cells infected with BtrusII were only produced fusion protein, but the polyhedra formed by fusion protein was not observed. To determine the insecticidal toxicity of fusion protein, therefore, Sf9 cells infected with BtrusI were inoculated to Bombyx mori larvae. Sf9 cells infected with BtrusI that expressed the fusion protein caused larval mortality although the insecticidal toxicity was low. In conclusion, our results clearly demonstrated that the fusion protein with polyhedrin and Bt cryIA(c) crystal protein have a insecticida toxicity.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1031-1035
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• 2004

The adsorption kinetics of ${\beta}$-casein on a hydrophobic surface has been studied by means of the quartz crystal microbalance (QCM). The self assembled monolayer of 1-octadecanethiol on a gold coated quartz crystal was used as a hydrophobic surface for adsorption. The adsorption kinetics was monitored in different solution conditions. Formation of monolayer is observed in most cases. At high concentration of protein, micelle formation which is interrupted by high ionic strength of solution is observed. Casein binding cations such as $Ca^{2+},\;Ba^{2+}\;and\;Al^{3+}$ increase the hydrophobicity of the protein and the multiple layer adsorption occurs. The strong and weak points of the QCM method in the study of protein adsorption are discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.1-7
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• 2000

Early studies of the molecular biology of Bacillus thuringeinsis suggested that genetic manipulation of this species could create combinations of genes more useful than those known to occur in natural isolates. Breakthroughs that made these manipulations possible include the cloning of many genes encoding endotoxins, the development of transformation vectors, and various PCR techniques. This paper reviews several genetic factors such as promoters, a 5'mRNA stabilizing sequence, 3'transcription termination sequences, and helper proteins that have been used to enhance crystal protein synthesis, and shows how these genetic elements can be manipulated with new molecular tools to develop more efficacious strains of B. thuringiensis.

• Journal of Life Science
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• v.10 no.4
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• pp.333-339
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• 2000

To identify genes involved in the decolorization of crystal violet, we isolated random mutants generated by transponson insertion in crystal violet-declorizing bacterium, Citrobacter sp. The resulting mutant bank yielded mutants with six distinct phenotypes, and Southern hybridization with a Tn5 fragment as a probe showed a single hybridized with six distinct phenotypes, and Southern hybridization with a Tn5 fragment as a probe showed a single hybridized band in the mutants Ctg 2, 5 an 6, whereas two and three bands were detected in Ctg1, 4 and 3, respectively. Tn5-inserted genes were isolated and the DNA sequence flanking Tn5 was determined. From comparison with a sequence database, putative protein product encoded by ctg 5 was identified as E. coli maltose transproter(Mal G) homolog, whereas the deduced amino acid sequence of the other ctg genes did not show any significant similarity with any DNA or protein sequency. Therefore, these results indicate that the other ctg genes except ctg 5 encode new proteins responsible for decolorization of crystal violet.

• Proceedings of the Korea Crystallographic Association Conference
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• 2000.11a
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• pp.7-7
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• 2000

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.1-6
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• 1999

A piezoelectric (PZ) biosensor system detecting Salmonella spp. was developed. The system consisted of an oscillator, a frequency counter and an antibody-immobilized quartz crystal. An anti-Salmonella antibody was immobilized on one gold. surface of the quartz crystal with protein A. Salmonella detection was made by measuring resonant frequency shift owing to a mass change by specific binding of microbial cells to the gold surface of the PZ crystal. The PZ antibody sensor was operated optimally at 0.1M phosphate buffer, pH 7.2 and $35^{\circ}C$. The sensor was quite specific to Salmonella spp. The obtained frequency shift was correlated with the Salmonella concentration in the range of $10^5{\sim}10^6\;CFU/mL$. The frequency shift increased further by addition of polystyrene beads. The Salmonella detection which is indicated by a steady-state microbial adsorption to the quartz crystal was accomplished within 50min.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.89-93
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• 2004

Expression of a fusion protein between B. thuringiensis crystal protein, Cry1Ac1 and a scorpion insect toxin (AaIT, Androctonus australis Hector insect toxin) in acrystalliferous B. thuringiensis strain (Cry-B strain) was examined. The cry 1Ac1 gene was cloned in B. thuringiensis-E coli shuttle vector, pHT3101, under the control of the native cry 1Ac1 gene promoter (pProAc) and a gene encoding AaIT was inserted in XhoI site in the middle of the cry 1Ac1 gene (pProAc-ScoR). B. thuringiensis Cry-B strain carrying pProAc-ScoR (PyoAc-ScoR/CB) produced an inclusion body of irregular shape and the expressed fusion protein is approximately 65 kDa in size. Sporulated cells and spore-crystal mixtures of ProAc-ScoR/CB had insecticidal activity against Plutella xylostella larvae, showing $LT_50$ of ProAc-ScoR/CB (22.59 hrs) lower than that of ProAc/CB (30.06 hrs) at $1{\times}{10^7} {CEU/cm^2}$. These results suggest that the fusion protein including a B. thuringiensis crystal protein and an AaIT may be functionally expressed in B. thupingiensis. Moreover, we verified the additive toxicity of AaIT, which is a new feasible candidate for insect control.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.31-32
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• 2003

Bacillus thuringiensis produces insecticidal parasporal inclusions (crystal protein) used as a major ingredient of most microbial insecticides. Although many B. thuringiensis strains and their crystal proteins have been isolated and characterized, such findings have limitation of usefulness. For enhanced toxicity, fast effects, and the delay of resistance development, research on genetic manipulation of crystal genes and proteins by genetic engineering should be continued. (omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.118-119
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• 2003

Baculovirus occlusion bodies have been recently engineered to incorporate foreign protein such as the Bacillus thuringiensis (Bt) CrylAc protein for improvement of insecticidal activity. In this study, polyhedrin, cylAc, egfp and crylCa genes were fused to produce occlusion bodies that contain novel recombinant crystal protein by homologous recombination between cylAc and crylCa genes in insect cells. (omitted)

• BMB Reports
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• v.45 no.12
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• pp.693-699
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• 2012

Together with protein tyrosine kinases (PTKs), protein tyrosine phosphatases (PTPs) serve as hallmarks in cellular signal transduction by controlling the reversible phosphorylation of their substrates. The human genome is estimated to encode more than 100 PTPs, which can be divided into eleven sub-groups according to their structural and functional characteristics. All the crystal structures of catalytic domains of sub-groups have been elucidated, enabling us to understand their precise catalytic mechanism and to compare their structures across all sub-groups. In this review, I describe the structure and mechanism of catalytic domains of PTPs in the structural context.