• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.780-786
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• 2002

An immunosensor based on surface plasmon resonance (SPR) with a self-assembled protein G layer was developed for the detection of Escherichia coli O157:H7. A self-assembled protein C layer on a gold (Au) surface was fabricated by adsorbing the mixture of 11-mercaptoundecanoic acid (MUA) and hexanethiol at various molar ratios and by activating chemical binding between free amine (-$NH_2$) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC) in series. The formation of a self-assembled protein G layer on an Au substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The surface morphology analyses of the self-assembled protein G layer on the Au substrate, monoclonal antibody (Mab) against E. coli O157:H7 which was immobilized on protein G, and bound E. coli O157:H7 extracts on Immobilized Mab against E. coii O157:H7 were performed by atomic force microscopy (AFM). The detection limit of the SPR-based immunosensor for E. coli O157:H7 was found to be about $10^4$ cells/ml.

• Proceedings of the Korean Society of Computer Information Conference
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• 2009.01a
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• pp.77-84
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• 2009

Intracellular signal transduction is achieved by protein-protein interaction. In this paper, we suggest performance algorithm based on Yeast protein-protein interaction and protein location information. We compare if pathways predicted with high valued weights indicate similar tendency with pathways provided in KEGG.

• The KIPS Transactions:PartB
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• v.12B no.3 s.99
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• pp.239-246
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• 2005

Biologist must have to do 2DGE biological experiment for Protein Search and Analysis. This experiment coming into being 2 dimensional image. 2DGE (2D Gel Electrophoresis : two dimensional gel electrophoresis) image is the most widely used method for isolating of the objective protein by comparative analysis of the protein spot pattern in the gel plane. The process of protein spot analysis, firstly segment protein spots that are spread in 2D gel plane by image processing and can find important protein spots through comparative analysis with protein pattern of contrast group. In the algorithm which detect protein spots, previous 2DGE image analysis is applies gaussian fitting, however recently Watersheds region based segmentation algorithm, which is based on morphological segmentation is applied. Watersheds has the benefit that segment rapidly needed field in big sized image, however has under-segmentation and over-segmentation of spot area when gray level is continuous. The drawback was somewhat solved by marker point institution, but needs the split and merge process. This paper introduces a novel marker search of protein spots by watersheds-based hierarchical threshold, which can resolve the problem of marker-driven watersheds.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.2
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• pp.133-148
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• 2005

Since understanding of similarities and differences among protein structures is very important for the study of the relationship between structure and function, many protein structure comparison systems have been developed. Hut, unfortunately, these systems introduce their own protein data derived from the PDB(Protein Data Bank), which are needed in their algorithms for comparing protein structures. In addition, according to the rapid increase in the size of PDB, these systems require much more computation to search for common substructures in their databases. In this paper, we introduce a protein structure comparison system named WS4E(A Web-Based Searching Substructures of Secondary Structure Elements) based on a PSAML database which stores PSAML documents using the eXist open XML DBMS. PSAML(Protein Structure Abstraction Markup Language) is an XML representation of protein data, describing a protein structure as the secondary structures of the protein and their relationships. Using the PSAML database, the WS4E provides web services searching for common substructures among proteins represented in PSAML. In addition, to reduce the number of candidate protein structures to be compared in the PSAML database, we used topology strings which contain the spatial information of secondary structures in a protein.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.5
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• pp.427-435
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• 2005

With the accumulation of protein and its related data on the Internet, many domain based computational techniques to predict protein interactions have been developed. However, most of the techniques still have many limitations to be used in real fields. They usually suffer from a low accuracy problem in prediction and do not provide any interaction possibility ranking method for multiple protein pairs. In this paper, we reevaluate a domain combination based protein interaction prediction method and develop an interaction possibility ranking method for multiple protein pairs. Probability equations are devised and proposed in the framework of domain combination based protein interaction prediction method. Using the ranking method, one can discern which protein pair is more probable to interact with each other than other protein pairs in multiple protein pairs. In the validation of the ranking method, we revealed that there exist some correlations between the interacting probability and the precision of the prediction in case of the protein pair group having the matching PIP(Primary Interaction Probability) values in the interacting or non interacting PIP distributions.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.3
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• pp.155-162
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• 2018

Infant formula is classified into standard cow's milk-based and special formulas. This review aimed at summarizing the types of special milk formulas currently sold in Korea, and the appropriate indications for the use of these formulas; lactose free formula, soy-based formula, protein hydrolysate formula, amino acid-based formula, preterm formula, medium chain triglyceride formula, low-phosphorus formula, protein-energy-enriched formula, and formulas for inborn errors of metabolism.

• Journal of Dairy Science and Biotechnology
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• v.25 no.1
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• pp.1-7
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• 2007

A Whey-based medium was formulated with Lactobacillus brevis to investigate whether any functional peptides could derive from whey protein. The optimal concentrations of the ingredients of the medium for the growth of Lactobacillus were determined as 2% whey protein concentrate and 1% glucose and 0.5% yeast extracts. The growth of Lb. brevis was improved with the supplementation of yeast extracts than glucose. The viable cells counts of Lb. brevis reached to 2.0 × 10$^8$CFU/mL in the whey-based medium. The whey protein hydrolysates recovered from the supernatant after centrifugation at 10,000 x g for 10min induced strong inhibitory activity against ACE. When the whey protein hydrolysate were partially purified by a membrane tubing below 8,000Da, the partially purified fraction remained 64.7 ${\pm}$ 3.6% of the ACE inhibition activity of the whey protein hydrolysates and IC$_{50}$ was 38.8 ${\pm}$ 2.2mg/mL. The whey-based medium was proved to be effective in producing ACE inhibitory peptides by lactic bacteria fermented whey protein.

• Journal of Animal Science and Technology
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• v.63 no.5
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• pp.1182-1193
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• 2021

The aims of this study were to develop a milk protein-based probiotic delivery system using a modified rennet-induced gelation method and to determine how the skim milk powder concentration level and pH, which can affect the rennet-induced intra- and inter-molecular association of milk proteins, affect the physicochemical properties of the probiotic delivery systems, such as the particle size, size distribution, encapsulation efficiency, and viability of probiotics in simulated gastrointestinal tract. To prepare a milk protein-based delivery system, skim milk powder was used as a source of milk proteins with various concentration levels from 3 to 10% (w/w) and rennet was added to skim milk solutions followed by adjustment of pH from 5.4 or 6.2. Lactobacillus rhamnosus GG was used as a probiotic culture. In confocal laser scanning microscopic images, globular particles with a size ranging from 10 ㎛ to 20 ㎛ were observed, indicating that milk protein-based probiotic delivery systems were successfully created. When the skim milk powder concentration was increased from 3 to 10% (w/w), the size of the delivery system was significantly (p < 0.05) increased from 27.5 to 44.4 ㎛, while a significant (p < 0.05) increase in size from 26.3 to 34.5 ㎛ was observed as the pH was increased from 5.4 to 6.4. An increase in skim milk powder concentration level and a decrease in pH led to a significant (p < 0.05) increase in the encapsulation efficiency of probiotics. The viability of probiotics in a simulated stomach condition was increased when probiotics were encapsulated in milk protein-based delivery systems. An increase in the skim milk powder concentration and a decrease in pH resulted in an increase in the viability of probiotics in simulated stomach conditions. It was concluded that the protein content by modulating skim milk powder concentration level and pH were the key manufacturing variables affecting the physicochemical properties of milk protein-based probiotic delivery systems.

• 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.

• The KIPS Transactions:PartB
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• v.13B no.1 s.104
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• pp.1-6
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• 2006

The prediction of protein function basically make use of a protein-protein interaction map based on the concept of guilt-by-association. The method however cannot determine the functions of proteins in case that the target protein does not interact with proteins with known functions directly. This paper studies protein function prediction considering the given problem as a K-class classification problem and proposes a predictive approach utilizing a modular neural network. The proposed method uses interaction data and protein related attributes as well. The experimental results demonstrate that the proposed approach can predict the functional roles of Yeast proteins whose interaction knowledge is not known and shows better performance than the graph-based models that use protein interaction data.