• Applied Biological Chemistry
• /
• v.49 no.4
• /
• pp.304-308
• /
• 2006

To extract insoluble proteins from silkworm pupa meal, the meal was treated with pretense produced by Bacillus sp. JH-209. The extraction of insoluble silkworm pupa protein was enhanced at alkaline pHs ranged from 7 to 11 by treatment with the protease. The optimum extraction temperature was $40^{\circ}C$ for in soluble protein treated with pretense. The optimum protease treatment time for extraction of protein was 11 hrs and optimum amount of enzyme treated for extraction of protein was 60 Unit, respectively. The treatment of enzyme extracted more protein than ordinary extraction method without pretense. The foaming capacity, foaming stability, emulsion capacity, and emulsion stability of silkworm pupa meal protein extracted by the treatment of the enzymes increased at all pH ranges. Further more oil absorption as well as water absorption capacities of the protein extracted by the treatment of the enzymes were also increased.

• Microbiology and Biotechnology Letters
• /
• v.17 no.4
• /
• pp.295-300
• /
• 1989

Screening of Pseudomonas strains that can be used as hosts for expression of crystal protein gene of Bacillus thuringiensis subsp. kurstaki HD-73 was carried out. From rhizosphere soil of 7 kinds or crops as fluorescent Pseudomonas strains were isolated. A hybrie plasmid, pKTC1, composed of the broad host range vector pKT230 and the crystal protein gene was constructed and used for transformation of the 35 Pseudomonas strains. As the result, the crystal protein gene could be introduced into 4 isolates. Several methods including bioassay and immunochemical detection indicated that the crystall protein gene was expressed in the Pseudomonus isolates.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.8 no.2
• /
• pp.112-116
• /
• 2003

An immunosensor based on surface plasmon resonance (SPR) onto a protein G layer by Self-assembly technique was developed for detection of Legionella pneumophila. The protein G layer by self-assembly technique was fabricated on a gold (Au) surface by adsorbing the 11-mercaptoundecanoic acid (MUA) and an activation process for the chemical binding of the free amino (-NH$_2$) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC) in series. The formation of the protein G layer by self-assembly technique on the Au Substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The Surface topographies of the fabricated thin films on an Au substrate were also analyzed by using an atomic force microscope (AFM). Consequently, an immunosensor for the detection of L. pneumophila using SPR was developed with a detection limit of up to 10$^2$CFU per mL.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.1
• /
• pp.26-32
• /
• 2018

The protein secondary structures are important information for studying the evolution, structure and function of proteins. Recently, deep learning methods have been actively applied to predict the secondary structure of proteins using only protein sequence information. In these methods, widely used input features are protein profiles transformed from protein sequences. In this paper, to obtain an effective protein profiles, protein profiles were constructed using protein sequence search methods such as PSI-BLAST and HHblits. We adjust the similarity threshold for determining the homologous protein sequence used in constructing the protein profile and the number of iterations of the profile construction using the homologous sequence information. We used the protein profiles as inputs to convolutional neural networks and recurrent neural networks to predict the secondary structures. The protein profile that was created by adding evolutionary information only once was effective.

• Macromolecular Research
• /
• v.17 no.6
• /
• pp.424-429
• /
• 2009

In this study, we demonstrate that the biological unnatural amino acid incorporation method can be utilized in vivo to synthesize an alkyne-terminated telechelic protein, Synthesis of terminally-functionalized polymers such as telechelic polymers is recognized to be important, since they can be employed usefully in many areas of biology and material science, such as drug delivery, colloidal dispersion, surface modification, and formation of polymer network. The introduction of alkyne groups into polymeric material is particularly interesting since the alkyne group can be a linker to combine other materials using click chemistry. To synthesize the telechelic recombinant protein, we attempted to incorporate the L-homopropargylglycine into the recombinant GroES fragment by expressing the recombinant gene encoding Met at the codons for both N- and C-terminals of the protein in the Met auxotrophic E. coli via Hpg supplementation. The Hpg incorporation rate was investigated and the incorporation was confirmed by MALDI-TOF analysis of the telcchelic recombinant protein.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.4
• /
• pp.638-644
• /
• 2018

In this study, the immobilization of xylanase using a protein-inorganic hybrid nanoflower system was assessed to improve the enzyme properties. The synthesis of hybrid xylanase nanoflowers was very effective at $4^{\circ}C$ for 72 h, using 0.25 mg/ml protein, and efficient immobilization of xylanase was observed, with a maximum encapsulation yield and relative activity of 78.5% and 148%, respectively. Immobilized xylanase showed high residual activity at broad pH and temperature ranges. Using birchwood xylan as a substrate, the $V_{max}$ and $K_m$ values of xylanase nanoflowers were 1.60 mg/ml and $455{\mu}mol/min/mg$ protein, compared with 1.42 mg/ml and $300{\mu}mol/min/mg$ protein, respectively, for the free enzyme. After 5 and 10 cycles of reuse, the xylanase nanoflowers retained 87.5% and 75.8% residual activity, respectively. These results demonstrate that xylanase immobilization using a proteininorganic hybrid nanoflower system is an effective approach for its potential biotechnological applications.

• BMB Reports
• /
• v.49 no.8
• /
• pp.437-442
• /
• 2016

We aimed to study the role of protein L-isoaspartyl methyltransferase (PIMT) in neuronal differentiation using basic fibroblast growth factor (bFGF)-induced neuronal differentiation, characterized by cell-body shrinkage, long neurite outgrowth, and expression of neuronal differentiation markers light and medium neurofilaments (NF). The bFGF-mediated neuronal differentiation of PC12 cells was induced through activation of mitogen-activated protein kinase (MAPK) signaling molecules [MAPK kinase 1/2 (MEK1/2), extracellular signal-regulated kinase 1/2 (ERK1/2), and p90RSK], and phosphatidylinositide 3-kinase (PI3K)/Akt signaling molecules PI3Kp110β, PI3Kp110γ, Akt, and mTOR. Inhibitors (adenosine dialdehyde and S-adenosylhomocysteine) of protein methylation suppressed bFGF-mediated neuronal differentiation of PC12 cells. PIMT-eficiency caused by PIMT-specific siRNA inhibited neuronal differentiation of PC12 cells by suppressing phosphorylation of MEK1/2 and ERK1/2 in the MAPK signaling pathway and Akt and mTOR in the PI3K/Akt signaling pathway. Therefore, these results suggested that PIMT was critical for bFGF-mediated neuronal differentiation of PC12 cells and regulated the MAPK and Akt signaling pathways.

• Journal of Pharmaceutical Investigation
• /
• v.40 no.2
• /
• pp.73-78
• /
• 2010

Hydrogels are thought to be a promising delivery carrier for protein drugs because of their favorable aqueous environment compared with nano/micro-particles of hydrophobic polymer such as PLGA. In this study, nano-sized hydrogels (nanogels) were fabricated using inverse-miniemulsion polymerization method. The mean size of nanogels in range of 90-160nm and affected by the preparation parameters such as sonication time and concentration of monomer. While longer sonication time and lower concentration of acrylamide monomer showed a tendency to produce smaller nanogels and to have lower lysozyme activity, variation of bis-methylene acrylamide concentration made no difference. Although both longer soncaton time and lower acrylamide concentration increased in vitro release rate, acrylamide concentration was more effectively affected to the control of protein release rate, which indicated that the release rate of protein from nanogels affected by not only their size but also internal structure. In conclusion, nanogels prepared by inverse-miniemulsion can be a useful carrier for application of protein drug, because of simple process, minimum contact of organic solvent and high protein activity.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2004.11a
• /
• pp.234-243
• /
• 2004

단백질-단백질 상호작용(PPI :Protein-Protein Interaction) 데이터는 생물체가 어떠한 메커니즘으로 생명을 유지하는지에 대한 정보를 담고 있다. 최근에는 생물학자들의 실험에 의해 많은 데이터가 축적되어 있으며, 데이터베이스로 구축되어 인터넷에 공개되어 있다. PPI 데이터는 단백질를 노드(node)로, 상호작용은 에지(edge)로 갖는 그래프(Graph) 구조로 표현 가능하다. 본 논문에서는 사용자가 PPI 데이터를 쉽게 가공하고 분석할 수 있도록 그래프 이론 기반에 기반하여 구현한 Proteinca(PROTEin INteraction CAbaret) 시스템에 대해 소개한다. Proteinca에 대한 자세한 정보는 http://jade.cs.pusan.ac.kr/${\sim}$proten에서 볼 수 있다.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.11 no.5
• /
• pp.420-424
• /
• 2006

A simple method for depleting E. coliS30 extracts of endogenous tRNA has been developed. An $ethanolamine-Sepharose^{(R)}$ column equilibrated with water selectively captured the tRNA molecules in E. coli S30 extracts. As a result, S30 extracts filtered through this column became completely dependent upon the addition of exogenous tRNA to mediate cell-free protein synthesis reactions. We anticipate that the procedures developed and described will be particularly useful for in vitro suppression reaction studies designed to introduce unnatural amino acids into protein molecules.