• Journal of Microbiology and Biotechnology
• /
• v.29 no.2
• /
• pp.268-273
• /
• 2019

The specificity of a Bacillus licheniformis uridine diphosphate (UDP) glycosyltransferase, YjiC, was increased towards thymidine diphosphate (TDP)-sugar by site-directed mutagenesis. The Arg-282 of YjiC was identified and investigated by substituting with Trp. Conversion rate and kinetic parameters were compared between YjiC and its variants with several acceptor substrates such as 7-hydroxyflavone (7-HF), 4',7-dihydroxyisoflavone, 7,8-dihydroxyflavone and curcumin. Molecular docking of TDP-glucose and 7-HF with YjiC model showed pi-alkyl interaction with Arg-282 and His-14, and pi-pi interaction with $His^{14}$ and thymine ring. YjiC (H14A) variant lost its glucosylation activity with TDP-glucose validating significance of His-14 in binding of TDP-sugars.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.185.3-186
• /
• 2003

It is well-known that bisphenol A(BPA), an industrial raw material for polycarbonate and epoxy resins, shows estrogenic activity. Recent research from our laboratory has shown that SPA disrupts interaction between thyroid hormone and its receptor in a non-competitive manner, and alters the thyroid-hormone dependent expression of growth hormone(GH) and prolactin(PRL). (omitted)

• Proceedings of the Zoological Society Korea Conference
• /
• 1999.10b
• /
• pp.230.2-230
• /
• 1999

No Abstract, See Full Text

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2005.09a
• /
• pp.383-387
• /
• 2005

One of the most important issues in post-genome era is identifying functions of genes and understanding the interaction among them. Such interactions from complex biochemical pathways, which are very useful to understand the organism system. We present an integrated biochemical pathway database system with a set of software tools for reconstruction, visualization, and simulation of the pathways from the database. The novel features of the presented system include: (a) automatic integration of the heterogeneous biochemical pathway databases, (b) gene ontology for high quality of database in the integration and query (c) various biochemical simulations on the pathway database, (d) dynamic pathway reconstruction for the gene list or sequence data, (e) graphical tools which enable users to view the reconstructed pathways in a dynamic form, (f) importing/exporting SBML documents, a data exchange standard for systems biology.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.5
• /
• pp.867-878
• /
• 1994

A general overview of the lipid peroxidation and its nutritional significance are presented ,with emphasis on the reaction mechaisms, peroxidized products, further interaction and nutritional/biological deterioration in a series of oxidative process. Overall mechanism with various factors and elements for initiation , propagation and termination of free radical reaction is reviewed and the primary /secondary products of peroxidized lipids are defined. Since these products are potentially reactive substances that can cause deterioration of proteins /amino acids and vitamins (carotene, tocopherols and ascorbic acid etc), mechanism and actual damages of their deterioration in some foods and biological models are outlined. Especially , chemical changes caused by interaction of peroxidized products (related hydroperoxides, radicals and malonaldehye etc) and protein are emphasized here. And also, the detailed mechanisms on radical scavenging of the these vitamins which are the most prominent natural antioxidants are presented . Additionally , the possible roles of peroxidicaed lipids and their secondary products in the process of aging an carcinogenesis are briefly discussed . However, it is important to not that more detailed and integrated studies on the reaction kinetics, energetics of peroxidation, their decomposed products , biochemical interaction potential damaging/aging / carcinogenic effects, protection from their oxidative spoilage and novel antioxidants in food and heterogeneous biological systems will be essential in order to assessing the implication of lipid peroxidation to human nutrition and health.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.11
• /
• pp.3241-3246
• /
• 2010

NHERF ($Na^+/H^+$ exchanger regulatory factor) and E3KARP (NHE3 kinase A regulatory protein) play important roles in membrane targeting, trafficking and sorting of ion channels, transmembrane receptors and signaling proteins in many tissues. Each of these proteins contains two PDZ (PSD-95/Dlg-1/ZO-1) domains, which mediate the assembly of transmembrane and cytosolic proteins into functional signal transduction complexes. The interaction between NHERF and E3KARP was investigated by surface plasmon resonance spectroscopy (BIAcore), fluorescence measurement, His-tagged pull-down experiment, and size-exclusion column (SEC) chromatography. BIAcore experiments revealed that NHERF bound to E3KARP with an apparent $K_D$ of 7 nM. Fluorescence emission spectra of the NHERF-E3KARP complex suggested that the tight interaction between these proteins was accompanied by significant conformational changes in one or both. The CD spectra of NHERF and E3KARP show that the conformational changes of these proteins were dependent on pH and temperature. These results implicate that the NHERF-E3KARP complex allows intracellular signaling complexes to form through PDZ-PDZ interactions.

• Biomolecules & Therapeutics
• /
• v.28 no.1
• /
• pp.18-24
• /
• 2020

Notable progress has been made in the therapeutic and research applications of cyclic peptides since our previous review. New drugs based on cyclic peptides are entering the market, such as plecanatide, a cyclic peptide approved by the United States Food and Drug Administration in 2017 for the treatment of chronic idiopathic constipation. In this review, we discuss recent developments in stapled peptides, prepared with the use of chemical linkers, and bicyclic/tricyclic peptides with more than two rings. These have widespread applications for clinical and research purposes: imaging, diagnostics, improvement of oral absorption, enzyme inhibition, development of receptor agonist/antagonist, and the modulation of protein-protein interaction or protein-RNA interaction. Many cyclic peptides are expected to emerge as therapeutics and biochemical tools.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.30 no.2
• /
• pp.58-63
• /
• 2015

An experimental rearing of tropical tasar silkworm, Antheraea mylitta Drury was conducted to study silkworm-food plant-interaction and thereby to search for an alternate silkworm food plant. The silkworm-food-plant-interaction was studied with six different food plant species viz. Terminalia tomentosa, Terminalia arjuna, Terminalia belerica, Terminalia chebula of Combretaceae family and Lagerstroemia speciosa, Lagerstroemia parviflora of Lythraceae family. The rearing performance of silkworm on Lagerstroemia speciosa in terms of cocoons per DFL and silk ratio was found comparable with Terminalia tomentosa and Termonalia arjuna, the primary tasar silkworm food plant species. These three plant species also possessed better results in terms of physiological (leaf moisture content and net photosynthesis rate) and biochemical (Chlorophyll, protein, carbohydrate and crude fibre contents) characteristics to support silkworm rearing than Terminalia belerica, Terminalia chebula and Lagerstroemia parviflora. The correlation study between silkworm rearing performance and food plant's constituents indicates commercial perspective of Lagerstroemia speciosa as an alternate food plant for tasar silkworm rearing.

• Journal of KIISE:Databases
• /
• v.30 no.6
• /
• pp.573-584
• /
• 2003

Recent massive data generation by genomics and proteomics requires bioinformatic tools to extract the biological meaning from the massive results. Here we introduce ROSPath, a database system to deal with information on reactive oxygen species (ROS)-mediated cell signaling pathways. It provides a structured repository for handling pathway related data and tools for querying, displaying, and analyzing pathways. ROSPath data model provides the extensibility for representing incomplete knowledge and the accessibility for linking the existing biochemical databases via the Internet. For flexibility and efficient retrieval, hierarchically structured data model is defined by using the object-oriented model. There are two major data types in ROSPath data model: ‘bio entity’ and ‘interaction’. Bio entity represents a single biochemical entity: a protein or protein state involved in ROS cell-signaling pathways. Interaction, characterized by a list of inputs and outputs, describes various types of relationship among bio entities. Typical interactions are protein state transitions, chemical reactions, and protein-protein interactions. A complex network can be constructed from ROSPath data model and thus provides a foundation for describing and analyzing various biochemical processes.

• Microbiology and Biotechnology Letters
• /
• v.17 no.3
• /
• pp.219-223
• /
• 1989

Effect of antifoam agents, silicone oil and neolin 302, was investigated on the production of prodnisolone by microbial $\Delta$$^1$-Dehydrogenation of hydrocortisone. The microbial process was conduct-ed by using a pseudo-crystallofermentation. By the hydrophobic-hydrophobic interaction, the steroid crystals aggregated with the antifoam agents. The aggregation resulted in a decrease of total mass transter area of substrate particles which is proportional to the dissolution rate of the solid substrate, and it consequently led to a significant decrease of the bioconversion rate. The bioconversion with neolin proceeded more slowly than with silicone oil. Increase of the concentration of the antifoam agents also yielded a significant decrease of the bioconversion rate.