• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.359-363
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• 1995

The antigenic variation of B. thuringiensis subsp. satto have been investigated for 120 hours during sporulation and crystallization by using SDS-PAGE and Western blot. Most antigens of a vegetative cell were found to disappear as it was in sporulation and crystallization, but protein antigens of 46, 29, 27, and 21 kDa continued to be expressed. The new protein bands of 293, 138, 119, 75, and 68 kDa appeared on days 2 through 5 in modified GYS medium. They were thought to be involved in sporulation and crystallization. The protein of 138 kDa was found to be a major protein of both crystal and spore. The expression patterns were immunologically analyzed by Western blot. The polyclonal antisera against the intact crystal showed strong immunoreactivity to proteins with molecular masses of 293, 138, 68, and 46 kDa. The polyclonal antisera against the spore recognized proteins of 293, 138, 68, and 46 kDa. Both crystals and spores appeared to express the common protein antigens.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1788-1791
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• 2002

In the post-genome era. it is one of important research subject to Investigate the roles of the proteins in human body based on decoded genome information during Human Genome Project. In order to clarify them. it is necessary to analyze the structure of the protein crystals and their function. ' Crystallization is the beginning stage of protein structure determination process. There are some methods for structural analysis of the proteins, and general one is X-ray structural analysis method. In order to utilize this method for analyzing the protein crystal's structure, artificial protein crystallization is required. However, since artificial crystallizing work takes much time and manpower. the performance against its cost is still low. Therefore. we started to discuss to develop a supporting system for improving efficiency of the crystallization distinction procedure. In this paper, we examine to realize such supporting system for crystallization distinction using image-processing technique and report about our experimental result with many real protein solution images.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.553-556
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• 2009

We investigated an application of supramolecular protein, and demonstrated the metal induced lateral crystallization utilizing ferritins with Ni nanoparticles, named the "bio-nano-crystallization". So far, this method has required long time, because of this method condition based on the conventional solid phase crystallization. In this study, we applied the pulsed rapid thermal annealing to bio-nanocrystallization. As a result, we succeeded in the crystallization for a short time. We found that the TFTs characteristics were improved with decrease metal impieties in poly-Si thin films by this method.

• BMB Reports
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• v.41 no.5
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• pp.353-357
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• 2008

LRR family proteins play important roles in a variety of physiological processes. To facilitate their production and crystallization, we have invented a novel method termed "Hybrid LRR Technique". Using this technique, the first crystal structures of three TLR family proteins could be determined. In this review, design principles and application of the technique to protein crystallization will be summarized. For crystallization of TLRs, hagfish VLR receptors were chosen as the fusion partners and the TLR and the VLR fragments were fused at the conserved LxxLxLxxN motif to minimize local structural incompatibility. TLR-VLR hybridization did not disturb structures and functions of the target TLR proteins. The Hybrid LRR Technique is a general technique that can be applied to structural studies of other LRR proteins. It may also have broader application in biochemical and medical application of LRR proteins by modifying them without compromising their structural integrity.

• Korean Journal of Crystallography
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• v.14 no.1
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• pp.35-38
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• 2003

A simple multistep-concentration setting in capillaries was used to control the water-evaporation rate in vapor-diffusion protein crystallization. In the method used, a variety of evaporation rate curves were obtained by using the secondary precipitant solution referred to as “regulatory solution”, which is not directly exposed to the protein solution. The curves were applied to the crystallization of lysozyme as a model protein. The results clearly showed that crystal growth is dependent on the evaporation rate. Especially, the decoupling curves in which precipitant concentration in protein solutions increases to a certain point and then decreases to the equilibrium concentration gave the best crystals.

• BMB Reports
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• v.43 no.9
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• pp.609-613
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• 2010

The Dvl and Axin proteins, which are involved in the Wnt signaling pathway, each contain a conserved DIX domain in their sequences. The DIX domain mediates interaction between Dvl and Axin, which together play an important role in signal transduction. However, the extremely low production of DIX domain fragments in E. coli has prevented more widespread functional and structural studies. In this study, we demonstrate that the DIX domains of Dvl and Axin are expressed noticeably in a multi-cistronic system but not in a mono-cistronic system. Formation of the $DIX_{Dvl1}-DIX_{Axin1}$ complex was investigated by affinity chromatography, SEC and crystallization studies. Unstable DIX domains were stabilized by complexing with counterpart DIX domains. The results of the preliminary crystallization and diffraction of the $DIX_{Dvl1}-DIX_{Axin1}$ complex may prove useful for further crystallographic studies.

• KSBB Journal
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• v.30 no.6
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• pp.296-301
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• 2015

Eggshell-based biocomposites have become attractive due to their exquisite nanostructure and biological properties, which are mainly composed of highly organized calcium carbonate crystals controlled by organic macromolecules such as proteins and polysaccharides. Here, we designed the recombinant fusion protein of a putative eggshell matrix protein named as GG1234 and a fluorescent reporter protein of DsRed. The protein was successfully over-expressed in E. coli and purified by Ni-NTA affinity chromatography. In vitro calcium carbonate crystallization was conducted in the presence of the fusion protein, and morphological change was investigated. The protein inhibited the calcite growth in vitro, and spherical calcium carbonate micro-particles with the diameter of about $20-30{\mu}m$ were obtained. We expect that this study would be helpful for better understanding of eggshell-based biomineralization.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.18-23
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• 2007

Fe65, a neuron-specific adaptor protein, has two phosphotyrosine binding (PTB) domains. The second PTB (PTB2) domain interacts with intracellular domain fragment (AICD) of amyloid beta precursor protein (APP). Recent studies suggested that tile complex is composed of AICD and Fe65 transactivates genes that are responsible for neuronal cell death in Alzheimer's disease (AD). Therefore, a compound inhibiting the interaction between Fe65 and AICD can be a drug candidate to treat AD. However, it remains unclear how Fe65 recognizes AICD at a molecular level. Here, we report high-level production of the PTB2 domain of Fe65 in the baculovirus system. We found that the baculovirus system is an efficient method to obtain the Fe65 PTB2 domain, compared with the bacterial and mammalian expression systems. The purified recombinant protein was used for crystallization to determine its crystal structure helping to understand the molecular mechanism of Fe65-dependent signaling and to design its inhibitors.

• BMB Reports
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• v.42 no.11
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• pp.697-704
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• 2009

Membrane proteins play important roles in the biology of the cell, including intercellular communication and molecular transport. Their well-established importance notwithstanding, the high-resolution structures of membrane proteins remain elusive due to difficulties in protein expression, purification and crystallization. Thus, accurate prediction of membrane protein topology can increase the understanding of membrane protein function. Here, we provide a brief review of the diverse computational methods for predicting membrane protein structure and function, including recent progress and essential bioinformatics tools. Our hope is that this review will be instructive to users studying membrane protein biology in their choice of appropriate bioinformatics methods.

• Polymer(Korea)
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• v.33 no.3
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• pp.248-253
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• 2009

Blend films based on the poly($\varepsilon$-caprolactone) (PCL) and amphiphilic biodegradable polymer, poly(ethylene glycol) grafted poly($\varepsilon$-caprolactone) (PCL-g- PEG), were prepared with different blend ratios in order to develop new biomedical material. PCL was the main component in the blend. The miscibility and characteristics of the blends were investigated. The crystallization temperature of the blend shifted to high temperatures with an increase of the graft copolymer contents when the homopolymer PCL was the main component of the blend. The PEG side chain in the blend affected the crystallization rate of the PCL crystals in the blend and alternating extinction bands were observed by optical microscopy. The protein adhesion behavior of the film was influenced by the water uptake of the film.