• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1498-1503
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• 2007

To identify novel crystal proteins, Bacillus thuringiensis 2385-1 was isolated from Korean soil samples and characterized. The H-serotype of 2385-1 was identical to that of subsp. kenyae (H4a4c), and its crystal toxin was bipyramidal-shaped. However, 2385-1 showed a much higher toxicity towards Plutella xylostella and Spodoptera exigua larvae than subsp. kenyae. In addition, the crystal protein profile and plasmid DNA pattern of 2385-1 differed from those of subsp. kenyae. To verify the crystal protein gene types of 2385-1, a PCR-RFLP analysis was performed, and the results revealed that 2385-1 contained two novel cry1-type crystal protein genes, cryl-5 and cry1-12, in addition to the crylJal gene. The deduced amino acid sequences of cryl-5 and cry1-12 showed a 97.9% and 75.7% sequence similarity with the CrylAb and CrylJa crystal proteins, respectively. Among the novel crystal proteins, Cry1-5 showed a high toxicity towards P. xylostella and S. exigua larvae. In conclusion, B. thuringiensis 2385-1 is a new isolate in terms of its gene types, and should be a promising source for an insecticide to control lepidopteran larvae.

• 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)

• The Journal of Korean Society of Virology
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• v.29 no.3
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• pp.145-153
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• 1999

We have now constructed a novel recombinant baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV) producing polyhedra with Bacillus thuringiensis (Bt) CryIAc crystal protein. The recombinant polyhedra produced by the recombinant baculovirus, Btrus, in insect cells was characterized. The recombinant baculovirus has two independent transcription units in opposite orientations with two promoters, p10 or polyhedrin gene promoter each initiating transcription of either native polyhedrin or fusion protein with polyhedrin and Bt Cry1Ac crystal protein. Surprisingly, this recombinant baculovirus stably produced recombinant polyhedra which were nearly similar to those of wild-type AcNPV. The immunogold staining experiment showed that the recombinant polyhedra were assembled with polyhedrin and Bt Cry1Ac crystal protein, and contained virus particles. Insecticidal toxicity of recombinant polyhedra of Btrus to the fall webworm, Hyphantria cunea, was strikingly improved in comparison with the wild-type AcNPV.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.19-19
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• 2001

The genome sequencing has revealed a large number of proteins of unknown or little characterized functions that have been well conserved during evolution. It remains a great challenge to decipher the molecular and physiological functions of these proteins. One example of the evolutionarily conserved protein family with little understood function is the surE family.(omitted)

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.173-176
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• 2008

MJ0684 from Methanococcus jannaschii is a hypothetical protein belonging to the subfamily Ig of amino acid aminotransferases. In the present study, the crystal structure of MJ0684 has been determined at 2.2 resolution. It reveals that MJ0684 has an overall structure similar to subfamily Ig aminotransferases and its active site architecture is most similar to that of kynurenine aminotransferases among several kinds of aminotransferases in the subfamily Ig?. It has two hydrophobic active site residues conserved in the kynurenine aminotransferases for recognizing hydrophobic substrates. In addition, the absence of any basic residue for recognizing the side chain carboxylic group of the aspartate in the active site rules out the possibility that MJ0684 would act as an aspartate aminotransferase. These structural observations collectively imply that MJ0684 is a novel archaeal homolog of the subfamily Ig kynurenine aminotransferase.

• Applied Science and Convergence Technology
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• v.24 no.1
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• pp.1-8
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• 2015

Protein immobilization on a gold surface plays an important role in the usefulness of biosensors that utilize gold-coated surfaces such as surface plasmon resonance (SPR), quartz crystal microbalance (QCM), etc. For developing high performance biosensors, it is necessarily required that immobilized proteins must remain biologically active. Loss of protein activity and maintenance of its stability on transducer surfaces is directly associated with the choice of immobilization methods, affecting protein-protein interactions. During the past decade, a variety of strategies have been extensively developed for the effective immobilization of proteins in terms of the orientation, density, and stability of immobilized proteins on analytical devices operating on different principles. In this review, recent advances and novel strategies in protein immobilization technologies developed for biosensors are briefly discussed, thereby providing an useful information for the selection of appropriate immobilization approach.

• 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.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.15-15
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• 2003

To discover new drugs more quickly and more efficiently, pharmaceutical companies and biotechnology firms are increasingly turning to the genomics and the structural proteomics technologies. Structural-proteomics can provide a foundation for this through the determination and analysis for protein structure on a genomics scale. Among many structures determined by CGI, we will present with the representative examples drawn from our work on novel structures or complex structures of the disease-related proteins. The alpha subunit of Hypoxia-inducible factor (HIF) is targeted for degradation under normoxic conditions by an ubiquitin-ligase complex that recognizes a hydroxylated proline residue in HIF. Hydroxylation is catalysed by HIF prolyl 4-hydroxylases (HIFPH) which are fe(II) and 2-oxoglutarate (2-OG) dependent oxygenases. Here, we discuss the first crystal structure of the catalytic domain of HIFPH in complexes, with the Fe(II)/2-OG at 1.8Å. These structures suggest that the Ll region (residues 236-253), which is also conserved in mammals, form a 'lid' that closes over the active site. The structural and mutagenesis analyses allow us to provide a focus for understanding cellular responses to hypoxia and a target for the therapeutic manipulation.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.28-28
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• 2003

To discover new drugs more quickly and more efficiently, pharmaceutical companies and biotechnology firms are increasingly turning to the genomics and the structural proteomics technologies. Structural-proteomics can provide a foundation for this through the determination and analysis for protein structure on a genomics scale. Among many structures determined by CGI, we will present with the representative examples drawn from our work on novel structures or complex structures of the disease-related proteins. The alpha subunit of Hypoxia-inducible factor (HIF) is targeted for degradation under normoxic conditions by an ubiquitin-ligase complex that recognizes a hydroxylated proline residue in HIF, Hydroxylation is catalysed by HIF prolyl 4-hydroxylases (HIFPH) which are Fe(II) and 2-oxoglutarate (2-OG) dependent oxygenases. Here, we discuss the first crystal structure of the catalytic domain of HIFPH in complexes, with the Fe(II)/2-OG at 1.8 ${\AA}$. These structures suggest that the L1 region (residues 236-253), which is also conserved in mammals, form a ‘lid’ that closes over the active site. The structural and mutagenesis analyses allow us to provide a focus for understanding cellular responses to hypoxia and a target for the therapeutic manipulation.

• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.387-397
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• 2023

Cytochrome P450 (CYP) is a heme-containing enzyme that catalyzes hydroxylation reactions with various substrate molecules. Steroid hydroxylases are particularly useful for effectively introducing hydroxyl groups into a wide range of steroids in the pharmaceutical industry. This study reports a newly identified CYP steroid hydroxylase (BaCYP106A6) from the bacterium Bacillus sp. and characterizes it using an in vitro enzyme assay and structural investigation. Bioconversion assays indicated that BaCYP106A1 catalyzes the hydroxylation of progesterone and androstenedione, whereas no or low conversion was observed with 11β-hydroxysteroids such as cortisol, corticosterone, dexamethasone, and prednisolone. In addition, the crystal structure of BaCYP106A6 was determined at a resolution of 2.8 Å to investigate the configuration of the substrate-binding site and understand substrate preference. This structural characterization and comparison with other bacterial steroid hydroxylase CYPs allowed us to identify a unique Arg295 residue that may serve as the key residue for substrate specificity and regioselectivity in BaCYP106A6. This observation provides valuable background for further protein engineering to design commercially useful CYP steroid hydroxylases with different substrate specificities.